Chapter XXVII: Section IV: STICHOCYRTIDA, Haeckel, 1862, Monogr. d. Radiol., p. 280, 312 (2)

_Definition._--#Stichophormida# (vel Stichocyrtida multiradiata aperta) with ovate or spindle-shaped shell, bearing in its wall numerous lateral ribs, which are prolonged into terminal feet. Mouth constricted.

The genus _Artophormis_ and the following _Cyrtophormis_ differ from the two preceding genera in the ovate form of the shell, which tapers in breadth towards the constricted mouth. It differs from the similar _Alacorys_ in the greater number of the shell-joints, this being four or more.

1. _Artophormis horrida_, n. sp. (Pl. 75, fig. 2).

Shell slenderly ovate, spiny, with three deep strictures, twice as long as broad. Length of the four joints = 2 : 5 : 6 : 7. Whole surface covered with strong conical spines. Six prominent, longitudinal ribs, decurrent from the cephalis to the mouth, are armed with larger spines, which in the upper joints are directed upwards, in the lower downwards. The six ribs are prolonged over the constricted mouth into six stout, conical feet. Cephalis subspherical, with a conical horn and some smaller spines. Pores circular, of very different sizes.

{1459}_Dimensions._--Length of the shell (with four joints) 0.2, breadth 0.1. Length of the single joints, _a_ 0.02, _b_ 0.05, _c_ 0.06, _d_ 0.07.

_Habitat._--South Pacific, Station 300, depth 1375 fathoms.

2. _Artophormis costata_, n. sp.

Shell spindle-shaped, rough, with six distinct strictures, three times as long as broad. The length of the seven joints increases gradually; the last joint is twice as long as the fifth. Six prominent, radial ribs arise from the third stricture, and are prolonged into six slender, convergent, conical feet, as long as the sixth joint. Cephalis hemispherical, with a pyramidal horn of twice the length. Pores regular, circular.

_Dimensions._--Length of the shell (with seven joints) 0.24, breadth 0.08. Length of the last joint 0.05.

_Habitat._--South Pacific, Station 295, depth 1500 fathoms.

3. _Artophormis barbadensis_, Haeckel.

_Calocyclas barbadensis_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 66, Taf. xviii. fig. 8.

Shell slenderly ovate, smooth, with three sharp strictures, twice as long as broad. Length of the four joints = 1 : 2 : 3 : 2. Nine prominent longitudinal ribs arise from the third joint, and are prolonged into nine slender, conical, little convergent feet. Cephalis hemispherical, with a conical horn of the same length. Pores subregular, circular, twice as large in the third joint as in the second; the fourth joint bears above a circle of nine very large pores (alternate with the nine ribs), and below two or three circles of smaller pores (eighteen to twenty-seven in the circumference). Mouth somewhat constricted. The figure of Ehrenberg is incomplete, the horn of the cephalis and the nine feet being broken off.

_Dimensions._--Length of the shell (with four joints) 0.16, breadth 0.08. Length of the single joints, _a_ 0.02, _b_ 0.04, _c_ 0.06, _d_ 0.04.

_Habitat._--Fossil in Barbados.

Genus 639. _Cyrtophormis_,[256] n. gen.

_Definition._--#Stichophormida# (vel Stichocyrtida multiradiata aperta) with ovate or spindle-shaped shell, without lateral ribs. Mouth constricted, with a corona of terminal feet.

The genus _Cyrtophormis_ may be derived from the preceding _Artophormis_ by reduction of the lateral ribs, whilst the terminal feet (as their free prolongations) remain, and form a corona around the mouth. Sometimes also each constriction bears {1460}a corona of spines. It corresponds to _Calocyclas_ among the Tricyrtida and _Anthocyrtis_ among the Dicyrtida.

Subgenus 1. _Cyrtophormium_, Haeckel.

_Definition._--Shell with six (sometimes five or seven) feet on the peristome (three perradial alternate with three interradial).

1. _Cyrtophormis armata_, n. sp. (Pl. 78, fig. 17).

Shell spiny, spindle-shaped, with three annular septa. Length of the four joints = 3 : 4 : 5 : 6. The third joint is the broadest, being twice as broad as the constricted mouth. Pores irregular, roundish. Cephalis conical, armed with a bunch of strong, conical spines, and distinguished by double-contoured pores. Peristome with six (sometimes five or seven) triangular, vertical, parallel, or slightly divergent feet.

_Dimensions._--Length of the shell (with four joints) 0.18, breadth 0.09. Length of the single joints, _a_ 0.03, _b_ 0.04, _c_ 0.05, _d_ 0.06.

_Habitat._--Central Pacific, Station 266, depth 2750 fathoms.

2. _Cyrtophormis ovata_, n. sp.

Shell rough, ovate, very thick-walled, with three distinct strictures. Length of the four joints = 1 : 1 : 2 : 3. The fourth joint is the broadest, inversely hemispherical, and three times as broad as the constricted mouth. Pores regular, circular, hexagonally framed. Cephalis hemispherical, with a pyramidal horn of the same length. Peristome with a coronal of six short, conical, curved, outwardly convex teeth.

_Dimensions._--Length of the shell (with four joints) 0.2, breadth 0.14. Length of the single joints, _a_ 0.02, _b_ 0.03, _c_ 0.06, _d_ 0.09.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subgenus 2. _Cyrtophormiscus_, Haeckel.

_Definition._--Shell with nine (sometimes eight or ten) feet on the peristome (three perradial alternate with six interradial).

3. _Cyrtophormis cingulata_, n. sp. (Pl. 78, fig. 18).

Shell spiny, spindle-shaped, with three internal annular septa, and three external girdles of spines. The second and third joints are of nearly equal length, twice as broad as the first, and half as broad as the fourth joint. The third joint is the broadest, and twice as broad as the constricted mouth. Pores subregular, circular. Cephalis hemispherical, with a large apical horn, and {1461}a coronal of six strong ascending spines. Peristome beyond the stricture of the mouth somewhat dilated, with nine triangular, divergent teeth (broken off in the specimen figured).

_Dimensions._--Length of the shell (with four joints) 0.18, breadth 0.09. Length of the single joints, _a_ 0.02, _b_ 0.04, _c_ 0.04, _d_ 0.08.

_Habitat._--Western Tropical Pacific, Station 224, depth 1850 fathoms.

4. _Cyrtophormis aculeata_, n. sp.

Shell spiny, slenderly ovate, with five distinct strictures, each with a girdle of spines. The three middle joints are of nearly equal length, each half as long as the second, and one-third as long as the sixth joint. The fifth joint is the broadest, twice as broad as the constricted mouth. Pores regular, circular. Cephalis conical, with a bunch of strong, divergent spines. Peristome with nine strong, conical, vertical, parallel teeth.

_Dimensions._--Length of the shell (with six joints) 0.18, breadth 0.08. Length of the first joint 0.02, the second 0.04, the three following 0.02, the sixth 0.06.

_Habitat._--North Pacific, Station 241, depth 2300 fathoms.

5. _Cyrtophormis acutata_, Haeckel.

_Eucyrtidium acutatum_, Stöhr, 1880, Palæontogr., vol. xxvi. p. 105, Taf.
iv. fig. 11.

Shell rough, spindle-shaped, with six annular strictures. The third, fourth, and seventh joints are equal in length, three times as long as the first and the fifth joints. The fourth joint is the broadest, four times as broad as the constricted mouth. Pores irregular, roundish. Cephalis small, subspherical, with a short conical horn. Peristome with nine (?) irregular, triangular, little convergent teeth.

_Dimensions._--Length of the shell (with seven joints) 0.22, breadth 0.11. Length of the third, fourth, and seventh joints 0.04.

_Habitat._--Fossil in Tertiary rocks of Sicily; Grotte (Stöhr).

Subgenus 3. _Acanthocyrtis_, Haeckel.

_Definition._--Shell with numerous (twelve to twenty or more) terminal feet.

6. _Cyrtophormis cylindrica_, n. sp. (Pl. 77, fig. 17).

Shell rough, subcylindrical, with three annular septa. The fourth cylindrical joint is four times as long as the second and the third joints. These three joints are nearly equal in breadth. Pores small and numerous, almost square, in regular, transverse rows; two to three in the first joint, five to six in the second and in the third, fourteen to sixteen in the fourth joint. Cephalis flat, cap-shaped, with a short, pyramidal horn. Peristome half as broad as the shell, hyaline, with a coronal of numerous, very delicate, vertical feet.

{1462}_Dimensions._--Length of the shell (with four joints) 0.2, breadth, 0.08. Length of the single joints, _a_ 0.02, _b_ 0.03, _c_ 0.03, _d_ 0.12.

_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.

7. _Cyrtophormis corona_, n. sp. (Pl. 77, fig. 15).

Shell smooth, conical, ovate, with three deep strictures, about twice as long as broad. The fourth joint is the broadest, inflated, and three times as long as the second and the third joints. Pores small and numerous, circular, in regular, transverse rows; two in the first joint, four in the second and third, and ten in the fourth joint. Cephalis hemispherical, with a stout, pyramidal horn. Peristome two-thirds as broad as the fourth joint, with twelve to fifteen triangular, convergent teeth.

_Dimensions._--Length of the shell (with four joints) 0.16, breadth 0.08. Length of the single joints, _a_ 0.01, _b_ 0.03, _c_ 0.03, _d_ 0.09.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

8. _Cyrtophormis cornuta_, n. sp. (Pl. 77, fig. 18).

Shell thorny, spindle-shaped, with three distinct strictures. Length of the four joints = 2 : 4 : 3 : 5. The third joint is the broadest. Pores circular, of different sizes, in the three first joints double-contoured. Cephalis subspherical, with a large, conical horn of three times the length. The fourth joint is inversely conical, three times as broad as the constricted mouth. Peristome with a coronal of numerous (ten to twenty) irregular, thin, partly forked teeth.

_Dimensions._--Length of the shell (with four joints) 0.14, breadth 0.07. Length of the single joints, _a_ 0.02, _b_ 0.04, _c_ 0.03, _d_ 0.05.

_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.

9. _Cyrtophormis fimbriata_, Haeckel.

_Lithocampe fimbriata_, Stöhr, 1880, Palæontogr., vol. xxvi. p. 103, pl.
iv. fig. 3.

Shell rough, spindle-shaped, with six annular septa. The fifth joint is the longest, twice as long as each of the three preceding joints, and four times as long as the sixth. The fourth joint is the broadest, three times as broad as the constricted mouth. Pores small, regular, circular. Cephalis small, subspherical, with a small, conical horn (broken off in the specimen figured). Peristome with an irregular, double coronal of ten to twenty vertical teeth.

_Dimensions._--Length of the shell (with seven joints) 0.25, breadth 0.1. Length of the fifth joint 0.06, of each of the three preceding 0.03.

_Habitat._--Central Pacific, Station 268, depth 2900 fathoms; fossil in Sicily (Grotte, Caltanisetta).

10. _Cyrtophormis turrita_, n. sp.

Shell smooth, nearly conical, twice as long as broad, with twelve sharp strictures. The thirteen joints increase gradually in length and breadth. The last joint is much longer than any of {1463}the others, twice as long as the eleventh, and twice as broad as the ninth joint. The constricted mouth on its lower surface is only one-third as broad. Cephalis small, hemispherical, with a short, conical horn. Peristome with a coronal of twenty to thirty delicate, partly confluent, vertical teeth.

_Dimensions._--Length of the shell (with thirteen joints) 0.26, breadth 0.12.

_Habitat._--South-Eastern Pacific, Station 299 (off Valparaiso), depth 2160 fathoms.

11. _Cyrtophormis turricula_, n. sp. (Pl. 75, fig. 5).

Shell smooth, slender, tower-shaped, with fourteen distinct strictures. The ten first joints are nearly equal in length. The twelfth joint is the largest, three to four times as long as each of the preceding, and broader than all the others, twice as broad as the suddenly constricted mouth. Pores small and numerous, regular, circular, quincuncial. Cephalis small, subspherical, with a pyramidal horn of three times the length. Peristome with a coronal of twenty to thirty very delicate, partly confluent, short, vertical teeth.

_Dimensions._--Length of the shell (with fifteen joints) 0.3, breadth 0.1. Length of the twelfth joint 0.05.

_Habitat._--South-Eastern Pacific, Station 298 (off Valparaiso), depth 2225 fathoms.

Subfamily 2. STICHOPHÆNIDA, Haeckel, 1881, Prodromus, p. 439.

_Definition._--#Phormocampida# with the terminal mouth of the shell fenestrated (vel Stichocyrtida multiradiata clausa).

Genus 640. _Artophæna_,[257] Haeckel, 1881, Prodromus, p. 438.

_Definition._--#Stichophænida# (vel Stichocyrtida multiradiata clausa) with six radial ribs or wings.

The genus _Artophæna_ and the following genus _Stichophæna_ represent together the small subfamily of Stichophænida, or of those #Cyrtoidea# in which the multiradiate shell is composed of numerous (four or more) joints, and closed at the end by a lattice-plate. The number of the lateral, solid, or latticed appendages is six in _Artophæna_, nine in _Stichophæna_. They may have been derived either from the _Stichophormida_ by closure of the terminal mouth, or from the _Stichoperida_ by intercalation of three or six interradial appendages.

1. _Artophæna ærostatica_, n. sp. (Pl. 75, fig. 4).

Shell four-jointed, with three sharp strictures and internal septa. The fourth joint is subspherical, longer than the three first joints together, and twice as broad as these. The second joint is {1464}twice as long as the first and the third, and armed with six divergent, stout, pyramidal, radial spines or wings of the same length. Cephalis flat, cap-shaped, with an oblique pyramidal horn of twice the length. Pores regular, circular, hexagonally framed.

_Dimensions._--Length of the shell (with four joints) 0.18, breadth 0.12. Length of the single joints, _a_ 0.02, _b_ 0.04, _c_ 0.02, _d_ 0.1.

_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.

2. _Artophæna senaria_, n. sp.

Shell pear-shaped, with five distinct strictures. Length of the four middle joints little different. The fifth joint is the broadest. From the first stricture there arise six radial ribs, which at the fourth are prominent as six short, conical, divergent spines. The last joint is inversely hemispherical, twice as long as the preceding. Cephalis hemispherical, with a conical horn of the same length. Pores regular, circular.

_Dimensions._--Length of the shell (with six joints) 0.14, breadth 0.09; of each joint 0.02, of the last 0.04.

_Habitat._--Central Pacific, Station 273, depth 2350 fathoms.

3. _Artophæna hexalatractus_, n. sp.

Shell spindle-shaped, with three sharp strictures, and six triangular, latticed, divergent wings, which arise from the collar stricture and descend along the two middle joints. Their terminal points fall into the same plane as the basal end of the fourth inversely conical joint. Length of the four joints = 1 : 2 : 4 : 2. Cephalis hemispherical, with a conical horn of the same length. (Similar to _Theophæna hexaptera_, Pl. 68, fig. 13, but with three distinct internal annular septa, corresponding to the three external strictures.)

_Dimensions._--Length of the shell (with four joints) 0.18, breadth 0.08. Length of the four single joints, _a_ 0.02, _b_ 0.04, _c_ 0.08, _d_ 0.04.

_Habitat._--South Pacific (off Juan Fernandez), Station 300, depth 1375 fathoms.

4. _Artophæna hexapodiscus_, n. sp.

Shell ovate, without external strictures, but with five internal annular septa. Length of the six joints = 1 : 2 : 3 : 4 : 3 : 6. Cephalis hemispherical, with a stout conical horn of twice the length. The last joint is the broadest, inversely hemispherical. From the fourth and fifth joints arise six divergent ribs, which are prolonged over the fifth stricture into six triangular, divergent, fenestrated feet, about as long as the last joint. Pores in the upper half of the shell regular, circular, in the lower half irregular, roundish.

_Dimensions._--Length of the shell (with six joints) 0.2, breadth 0.12. Length of the single joints, _a_ 0.015, _b_ 0.025, _c_ 0.03, _d_ 0.04, _e_ 0.03, _f_ 0.06.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

{1465}Genus 641. _Stichophæna_,[258] Haeckel, 1881, Prodromus, p. 439.

_Definition._--#Stichophænida# (vel Stichocyrtida multiradiata clausa) with nine radial ribs or wings.

The genus _Stichophæna_ differs from the preceding _Artophæna_ in the typical number of the radial lateral appendages, being nine in the former, six in the latter. Usually these are simple ribs enclosed in the shell-wall, more rarely prominent wings.

Subgenus 1. _Stichophænidium_, Haeckel.

_Definition._--Last joint of the shell rounded, without basal spines.

1. _Stichophæna ritteriana_, n. sp. (Pl. 75, fig. 12).

Shell pear-shaped, twice as long as broad, with seven internal annular septa. The upper half is slenderly conical, composed of seven joints of nearly equal length, gradually increasing in breadth. The lower half is formed only by the eighth joint, which is very large, subglobose, inflated, and as long as the seven other joints together. The spherical cephalis bears a conical horn of the same length. From the thorax arise at equal distances nine radial ribs in the form of thin, triangular lamellæ, which attain their greatest height in the sixth joint, and form nine elegant, denticulate crests in the eighth joint. Pores small and numerous, subregular, circular. This beautiful species is dedicated to my honourable friend, Dr. Paul von Ritter, the magnanimous philanthropist and liberal protector of free science, who founded in the University of Jena the first professorial chair of Darwinism and phylogeny.

_Dimensions._--Length of the shell (with eight joints) 0.24, breadth 0.12. Length of each of the first seven joints 0.015; diameter of the subspherical last joint 0.12.

_Habitat._--South Pacific, Station 300 (off Juan Fernandez), depth 1375 fathoms.

2. _Stichophæna darwiniana_, n. sp.

Shell pear-shaped, twice as long as broad, with six distinct strictures. The last joint is the broadest and twice as long as the sixth, three times as long as each of the five preceding joints. The hemispherical cephalis bears a conical horn of twice the length. From the third joint arise nine radial ribs, which reach the sixth joint, but are not developed in the last hemispherical joint. Pores irregular, roundish.

_Dimensions._--Length of the shell (with seven joints) 0.2, breadth 0.1. Length of five first joints, each 0.018 to 0.022, of the sixth 0.03, of the seventh joint 0.06.

_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.

{1466}3. _Stichophæna goetheana_, n. sp.

Shell ovate, one and a half times as long as broad, rough, with five internal annular septa. The six joints gradually increase in length and breadth. The last joint is the broadest, and half as long as the five others together. The hemispherical cephalis bears a pyramidal horn of twice the length. From the thorax arise nine radial ribs, which attain their greatest height in the fourth joint and reach the fifth joint, but are not developed in the last ovate joint. Pores subregular, circular.

_Dimensions._--Length of the shell (with six joints) 0.22, breadth 0.14. Length of the single joints, _a_ 0.02, _b_ 0.025, _c_ 0.03, _d_ 0.035, _e_ 0.04, _f_ 0.7.

_Habitat._--Central Pacific, Station 266, depth 2750 fathoms.

Subgenus 2. _Stichophænoma_, Haeckel.

_Definition._--Last joint of the shell pointed, armed with a polar, basal spine, or a bunch of spines.

4. _Stichophæna nonaria_, n. sp. (Pl. 76, fig. 6).

Shell nearly spindle-shaped, with five or six distinct strictures. The third joint is the broadest and longest, and twice as long as the second and the fifth joints. Along the second or third middle joint (beginning from the second or third) descend nine prominent longitudinal ribs. Cephalis hemispherical, with two short, conical, divergent horns. Last joint inversely conical, armed with several strong, conical, divergent spines.

_Dimensions._--Length of the shell (with seven joints) 0.23, of the third joint 0.05, of the last 0.04; breadth 0.1.

_Habitat._--North Pacific, Station 244, depth 2900 fathoms.

5. _Stichophæna novena_, n. sp. (Pl. 76, fig. 7).

Shell nearly spindle-shaped, with eight or nine deep strictures. The third joint is the broadest, campanulate, in its lower half with nine prominent ribs, which disappear beyond the third stricture. The following joints are alternately longer and shorter, and decrease gradually in breadth. Thorax hemispherical. Cephalis small, hemispherical, with a conical horn of the same length. Last joint also hemispherical, scarcely larger than the cephalis, with a bunch of conical, divergent spines.

_Dimensions._--Length of the shell (with nine joints) 0.25, of the third joint 0.05, of the last 0.02; breadth 0.1.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

{1467}Family LXX. #LITHOCAMPIDA#, n. fam.

_Artocorida et Artocapsida_, _Stichocorida et Stichocapsida_, Haeckel,
1881, Prodromus, pp. 437-439.

_Definition._--#Stichocyrtida# eradiata. (#Cyrtoidea# with an annulated shell, divided by three or more transverse constrictions into four or more annular joints, without radial apophyses.)

The family #Lithocampida# comprises those #Cyrtoidea# in which the lattice-shell is composed of numerous (four to eight or more) annular joints, and bears no radial apophyses. It may be divided into two subfamilies, differing in the shape of the terminal mouth. This is a simple wide opening in the Stichocorida (and the united Artocorida), closed by a lattice-plate in the Stichocapsida (and the allied Artocapsida). The phylogenetic origin of the Lithocampida may be found in the Theocyrtida.

The number of species of Lithocampida is very great, and amounts here to more than one hundred and sixty whilst the total number of Stichocyrtida is about two hundred and forty. They represent therefore, two-thirds of the whole group, whilst one third is composed of the Podocampida and Phormocampida. Ehrenberg has already described between forty and fifty species in his genera _Eucyrtidium_ and _Lithocampe_; the majority of these were fossils from Barbados.

This large number of species may be easily increased by accurate researches on the great masses of Lithocampida, which are found in the Radiolarian ooze of the Challenger, and as fossils in Barbados. The variety in the number, size, and proportion of the shell-joints and of the lattice-pores is very great, and permits us to distinguish a far greater number of species than are here described. Many species are cosmopolitan, and belong to the most common forms of Radiolaria.

This large number of species requires to be disposed in different genera, but the distinction of these latter is a rather difficult task, since the exterior of the shell, as well as its internal structure, offers no striking differences (compare Pls. 78 to 80). In my Monograph (1862, pp. 312 to 319) I have already pointed out the difficulty of distinguishing between _Lithocampe_ and _Eucyrtidium_. The general form of the shell exhibits a continuous series of transformations, from a flat, conical, or nearly discoidal form, through cylindrical to ovate, or spindle-shaped shells, the wide open terminal mouth becoming more or less constricted, and finally (in the Stichocapsida) closed. The absence or presence of an apical horn may further serve for the distinction of genera. A peculiar small group is represented by the Spirocampida (_Spirocyrtis_, _Spirocampe_, Pl. 76, figs. 11 to 17), the transverse latticed girdles separating the single joints, which are usually parallel and horizontal, becoming here partly connected, so that they form a descending spiral.

{1468}_Synopsis of the Genera of Lithocampida._

-------------------------------------------------------------------------
I. Subfamily Stichocorida.
Terminal mouth of the last shell-joint a simple wide opening.
--------------------
All annular septa or transverse strictures of the shell separated,
parallel, not connected by a spiral line.
-------------------------------------------------------------------------
{ Conical, { With horn, 642. _Lithostrobus_.
Shell conical { gradually {
or cylindrical. { dilated. { No horn, 643. _Dictyomitra_.
Mouth of the {
last joint wide { Conical above, {
open, not { cylindrical { With horn, 644. _Stichocorys_.
distinctly { below. {
constricted. {
{ Cylindrical or { With horn, 645. _Artostrobus_.
{ subcylindrical. {
{ { No horn, 646. _Lithomitra_.

{ { Last joint
{ { not tubular, 647. _Eucyrtidium_.
{ Cephalis with {
Shell ovate or { a horn. { Last joint a
spindle-shaped. { { long tube, 648. _Eusyringium_.
Mouth of the {
last joint { { Cephalis with
constricted. { Cephalis { tube. 649. _Siphocampe_.
{ without horn. {
{ { Cephalis
{ { without tube, 650. _Lithocampe_.
-------------------------------------------------------------------------
Annular septa or transverse strictures of the shell all or partly
obliquely descending and connected spirally.
-------------------------------------------------------------------------
With horn, 651. _Spirocyrtis_.

No horn, 652. _Spirocampe_.
-------------------------------------------------------------------------
II. Subfamily Stichocapsida.
Terminal mouth closed by a lattice-plate.
-------------------------------------------------------------------------
Last joint rounded, without a { With horn, 653. _Cyrtocapsa_.
vertical basal spine. {
{ No horn, 654. _Stichocapsa_.

Last joint conical, pointed, with { Cephalis
a vertical, basal spine. { with horn, 655. _Artocapsa_.

Subfamily 1. STICHOCORIDA, Haeckel, 1881, Prodromus, p. 438.

_Definition._--#Lithocampida# with the terminal mouth of the shell open (vel Stichocyrtida eradiata aperta).

Genus 642. _Lithostrobus_,[259] Bütschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 529.

_Definition._--#Stichocorida# (vel Stichocyrtida eradiata aperta), with conical shell, gradually dilated towards the wide open mouth. Cephalis with a horn.

The genus _Lithostrobus_ is probably the most primitive among the Lithocampida, and comprises those forms of this family in which the slender, conical shell is gradually dilated towards the wide, terminal mouth, each joint being broader than the preceding. {1469}It may be derived from _Theoconus_ by increase in the number of the joints. Some species are distinguished by a curved axis, which gives them a horn-like appearance; these may be separated as a peculiar genus, _Cornustrobus_.

Subgenus 1. _Conostrobus_, Haeckel.

_Definition._--Shell regularly conical, with straight axis; all joints nearly equal in length, gradually increasing in breadth.

1. _Lithostrobus monostichus_, n. sp.

Shell slenderly conical, smooth, with straight axis, and eight to ten deep strictures. All joints nearly of the same length, gradually increasing in breadth; the eighth joint twice as broad as the fourth. In each joint only a single transverse series of small, circular, regular pores. Horn of the cephalis conical, straight, of twice the length. (Similar to _Lithostrobus tetrastichus_, Pl. 80, fig. 6, but in each joint there is only a single series of pores.)

_Dimensions._--Length of the shell (with ten joints) 0.2, of each joint 0.02; breadth of the fourth joint 0.03, of the eight 0.06.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. _Lithostrobus distichus_, n. sp.

Shell conical, papillate, with straight axis, and four to six deep strictures. All joints nearly of the same length, the fifth twice as broad as the second. In each joint two transverse rows of large, circular pores. Horn of the cephalis stout, straight, conical, of the same length.

_Dimensions._--Length of the shell (with six joints) 0.18, of each joint 0.03; breadth of the second joint 0.04, of the fifth 0.08.

_Habitat._--Central Pacific, Station 268, depth 2900 fathoms.

3. _Lithostrobus tristichus_, Haeckel.

_Lithostrobus cuspidatus_, Bütschli, 1882, Zeitschr. f. wiss. Zool., vol.
xxxvi. p. 529.

_Eucyrtidium cuspidatum_, Bailey, 1856, Amer. Journ. Sci. and Arts, vol.
xxii, p. 5, pl. i. fig. 12.

Shell slenderly conical, smooth, with straight axis, and eight to ten deep strictures. All joints nearly of the same length, the eighth joint twice as broad as the third. In each joint three transverse rows of pores. Horn of the cephalis bristle-shaped, strongly curved, about as long as the shell (Ehrenberg confounds this species with _Lithostrobus cuspidatus_).

_Dimensions._--Length of the shell (with eight joints) 0.16, of each joint 0.02; breadth of the fourth joint 0.04, of the eighth 0.08.

_Habitat._--North Pacific, Kamtschatka (Bailey); Station 241, depth 2300 fathoms.

{1470}4. _Lithostrobus tetrastichus_, n. sp. (Pl. 80, fig. 6).

Shell slenderly conical, smooth, with straight axis and six to eight deep strictures. All joints nearly of the same length, the eighth joint twice as broad as the second. In each joint four transverse rows of regular, circular pores with very thin bars. Horn of the cephalis conical, strong, curved, about as long as two joints.

_Dimensions._--Length of the shell (with eight joints) 0.12, of each joint 0.015; breadth of the second joint 0.02, of the eighth 0.04.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

5. _Lithostrobus pentastichus_, n. sp.

Shell slenderly conical, smooth, with straight axis, and six to eight slight strictures. All joints nearly of the same length, the sixth twice as broad as the third. In each joint five transverse rows of small circular pores. Horn of the cephalis pyramidal, of twice the length. (Similar to _Eucyrtidium cienkowskii_, Pl. 80, fig. 9, but regularly conical, with all the joints equal in length.)

_Dimensions._--Length of the shell (with eight joints) 0.2, of each joint 0.025; breadth of the third joint 0.04, of the sixth 0.08.

_Habitat._--South Pacific, Station 298, depth 2225 fathoms.

6. _Lithostrobus hexastichus_, n. sp. (Pl. 80, fig. 15).

Shell campanulate-conical, smooth, with straight axis, and six to eight slight strictures. All joints nearly of the same length, the sixth joint twice as broad as the second. In each joint six transverse rows of subregular, hexagonal pores, with thin bars. Horn of the cephalis conical, straight, of about the same length. (The specimen figured is a somewhat irregular one; other specimens found afterwards were perfectly conical and regular, with joints of equal length).

_Dimensions._--Length of the shell (with six joints) 0.16, of each joint 0.027.

_Habitat._--Central Pacific, Station 270 to 274, depth 2350 to 2925 fathoms.

Subgenus 2. _Cornustrobus_, Haeckel.

_Definition._--Shell horn-shaped, conical, with curved axis; all joints nearly equal in length, gradually increasing in breadth.

7. _Lithostrobus cyrtoceras_, n. sp. (Pl. 80, fig. 2).

Shell horn-shaped, conical, with curved axis, smooth, with six to eight deep strictures. All joints nearly of the same length, gradually increasing in breadth; the sixth joint twice as broad as the second. In each joint about four transverse series of regular circular pores. Horn of the cephalis conical, slightly curved, of the same length.

{1471}_Dimensions._--Length of the curved axis of the shell (with eight joints) 0.24, length of each joint 0.03; breadth of the second joint 0.04, of the sixth 0.08.

_Habitat._--Central Pacific, Station 271, depth 2425 fathoms.

8. _Lithostrobus leptoceras_, n. sp.

Shell horn-shaped, slenderly conical, with curved axis (like a quadrant of a circle), smooth, with twelve to fourteen slight strictures. All joints nearly of the same length, the tenth twice as broad as the second. In each joint only a single transverse row of small circular pores. Horn of the cephalis curved, bristle-shaped, half as long as the shell.

_Dimensions._--Length of the curved axis of the shell (with twelve joints) 0.18, length of each joint 0.15; breadth of the second joint 0.02, of the tenth 0.04.

_Habitat._--North Pacific, Station 253, depth 3125 fathoms.

9. _Lithostrobus caloceras_, n. sp. (Pl. 80, fig. 4).

Shell horn-shaped, conical, with curved axis, smooth, with six to eight deep strictures. All joints nearly of the same length, the sixth twice as broad as the third. On each joint a single circle of very large roundish pores, separated by two to four series of smaller pores. Horn of the cephalis conical, curved, of twice the length.

_Dimensions._--Length of the curved axis of the shell (with six joints) 0.12, length of each joint 0.02; breadth of the third joint 0.04, of the sixth 0.08.

_Habitat._--South Pacific, Station 297, depth 1775 fathoms.

10. _Lithostrobus macroceras_, n. sp.

Shell horn-shaped, slenderly conical, with curved, nearly semicircular axis, without external strictures, but with twelve to twenty internal septal rings. All joints nearly of the same length, the twelfth twice as broad as the third. On each joint three to four transverse rows of subregular, small, hexagonal pores. Horn of the cephalis conical, curved, of twice the length.

_Dimensions._--Length of the curved axis of the shell (with sixteen joints) 0.32, length of each joint 0.02; breadth of the third joint 0.02, of the twelfth 0.04.

_Habitat._--Central Pacific, Station 274, depth 2750 fathoms.

Subgenus 3. _Cyrtostrobus_, Haeckel.

_Definition._--Shell conical (often more campanulate or irregular), with straight axis; joints of different lengths. Cephalis not lobate.

{1472}11. _Lithostrobus conulus_, n. sp. (Pl. 80, fig. 1).

Shell slenderly conical, smooth, with straight axis, and seven to ten distinct strictures. Joints of different lengths; the fourth and fifth about twice as long as the preceding and following joints, the former with four to five, the latter with two to three transverse rows of large irregular pores; the seventh joint twice as broad as the third. Horn of the cephalis short, pyramidal.

_Dimensions._--Length of the shell (with eight joints) 0.14, length of the fifth joint 0.03; breadth 0.06.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

12. _Lithostrobus picus_, Bütschli.

_Lithostrobus picus_, Bütschli, 1882, Zeitschr. f. wiss. Zool., vol.
xxxvi. p. 529.

_Eucyrtidium picus_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 72, Taf. xi. fig. 1.

Shell slenderly conical, smooth, with straight axis, and six to eight slight strictures. Joints of different lengths, the second twice as long as each of the three following, and four times as long as each of the last joints; the sixth joint one and a-half times as broad as the second. Small circular pores in regular transverse rows; six rows in the first and the second, three rows in the third, fourth, and fifth, a single row in each of the last joints. Horn of the cephalis cylindrical, half as long as the shell.

_Dimensions._--Length of the shell (with eight joints) 0.12, length of the second joint 0.03; breadth 0.04.

_Habitat._--Fossil in Barbados.

13. _Lithostrobus argus_, Bütschli.

_Lithostrobus argus_, Bütschli, 1882, Zeitschr. f. wiss. Zool., vol.
xxxvi. p. 529.

_Eucyrtidium argus_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. ix. fig. 1.

Shell conical, thorny, with straight axis, and five to seven slight strictures. Joints of different lengths, each of the three first twice as long as each of the following. Pores large, roundish, in transverse rows; three rows in the first and the second joints (which in the figure of Ehrenberg are not separated), two rows in the third joint, a single row in each of the following joints. Horn of the cephalis large, conical, curved, half as long as the shell.

_Dimensions._--Length of the shell (with seven joints) 0.2, length of the fourth joint (and each following) 0.02; breadth 0.1.

_Habitat._--Fossil in Barbados.

14. _Lithostrobus acuminatus_, Haeckel.

_Eucyrtidium acuminatum_, Bury, 1862, Polycystins of Barbados, pl. i,
fig. 1.

Shell slenderly conical, smooth, with straight axis, and four to six deep strictures. Joints gradually increasing in length. Pores in regular, transverse rows, commonly three rows in the first, four {1473}in the second, five in the third, six in the fourth, seven in the fifth, &c. (sometimes the increase of the number is more or less irregular). Horn of the cephalis strong, conical, straight, about as long as the fourth or sixth joint.

_Dimensions._--Length of the shell (with six joints) 0.2; length of the fourth joint 0.04, breadth 0.06.

_Habitat._--Fossil in Barbados.

15. _Lithostrobus cuspidatus_, Haeckel.

_Eucyrtidium cuspidatum_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 291, Taf. ii. fig. 15.

Shell, slender, conical, smooth, with straight axis, and ten to twelve distinct strictures. Joints gradually increasing slightly in length, the tenth twice as long as the third. Pores circular, in regular transverse rows; commonly two rows in the first, three in the second, four in the third, seven in the eighth and following joints. Horn of the cephalis long, bristle-shaped, curved. This species called _Eucyrtidium cuspidatum_ by Ehrenberg, differs from _Lithostrobus tristichus_ (compare above), to which Bailey had given the same name.

_Dimensions._--Length of the shell (with ten joints) 0.2; length of the tenth joint 0.03, breadth 0.06.

_Habitat._--North Atlantic (Greenland, Ehrenberg); Station 348, depth 2450 fathoms.

16. _Lithostrobus cornutella_, Bütschli.

_Lithostrobus cornutella_, Bütschli, 1882, Zeitschr. f. wiss. Zool., vol.
xxxvi. p. 529.

_Eucyrtidium cornutella_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 291, Taf. ii. fig. 14.

Shell slender, conical, smooth, with straight axis, and seven to nine slight strictures. Joints gradually increasing slightly in length, the sixth or seventh about twice as long as the third. Pores circular, in regular transverse rows; two or three in the three or four first joints, three or four in the following, four or five in the last joints. Horn of the cephalis thin, bristle-shaped, curved.

_Dimensions._--Length of the shell (with eight joints) 0.1; length of the eighth joint 0.01, breadth 0.04.

_Habitat._--Cosmopolitan; Mediterranean, Atlantic, Pacific; many stations, surface.

17. _Lithostrobus tornatus_, Haeckel.

_Eucyrtidium tornatum_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 292, Taf. ix. fig. 20.

Shell campanulate-conical, smooth, with straight axis, and four to six deep strictures. Joints broad, gradually increasing in length, the fifth twice as long as the second. Pores small, circular, in regular transverse rows; in the second and third joints three or four rows, in the fifth seven rows, &c. Horn of the cephalis small, double or forked.

{1474}_Dimensions._--Length of the shell (with five joints) 0.1; length of the fifth joint 0.04, breadth 0.08.

_Habitat._--Indian Ocean, Zanzibar, depth 2200 fathoms (Pullen).

18. _Lithostrobus seriatus_, n. sp. (Pl. 79, fig. 15).

Shell slender, conical, smooth, with straight axis, and four or five deep strictures. Joints little different in length, increasing towards the inflated last joint, which is twice as long as the preceding. On each joint four or five transverse rows of small circular pores. Horn small, bristle-shaped, oblique. This common species is rather variable.

_Dimensions._--Length of the shell (with five joints) 0.14; length of the fifth joint 0.05, breadth 0.06.

_Habitat._--Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

19. _Lithostrobus cornutus_, n. sp. (Pl. 77, fig. 6).

Shell slender, conical, subcampanulate, smooth, with three or four deep strictures. Joints of different lengths, the third and the fourth twice as long as the second, four times as long as the first. Transverse rows of small circular pores; three in the first joint, five in the second, eight in the third and in the fourth. Horn large, pyramidal, about as long as the third joint.

_Dimensions._--Length of the shell (with four joints) 0.12; length of the third joint 0.04, breadth 0.06.

_Habitat._--Central Pacific, Station 265 to 268, depth 2700 to 2900 fathoms.

20. _Lithostrobus microporus_, Bütschli.

_Lithostrobus microporus_, Bütschli, 1882, Zeitschr. f. wiss. Zool., vol.
xxxvi. p. 529.

_Eucyrtidium microporum_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 291, Taf. xi. fig. 20.

Shell slender, conical, smooth, very similar to the preceding species, differs mainly in the more slender form and the smaller pores. The first joint has four, the second eight, the third ten transverse rows of pores. Horn conical, as long as the cephalis. The third joint in this and the preceding species is campanulate, and large.

_Dimensions._--Length of the shell (with four joints) 0.11; length of the third joint 0.05, breadth 0.04.

_Habitat._--Fossil in Barbados.

21. _Lithostrobus quadratus_, n. sp.

Shell broad, conical, smooth, with straight axis, and six to eight deep strictures. Joints of different lengths, usually alternately longer and shorter. The seventh joint five times as broad as long, twice as long as the sixth and the fourth; six transverse rows of pores in the seventh, three {1475}in the sixth joint. Horn small, conical. This species differs from all others in the subregular square form of the small pores.

_Dimensions._--Length of the shell (with seven joints) 0.15; length of the seventh joint 0.024, breadth 0.12.

_Habitat._--Central Pacific, Station 271 to 274, depth 2350 to 2750 fathoms.

22. _Lithostrobus hexagonalis_, n. sp. (Pl. 79, fig. 20).

Shell broad, conical, smooth, with straight axis, and five to eight prominent girdles between six and nine constricted broad joints. The first and the third joints are half as long as the second, the fourth, and each of the following joints. The sixth joint is five times as broad as long. Pores subregular, hexagonal, in regular transverse rows; three to four rows in the first and the second joints, six to eight in the third, the fourth, and each following joint. Cephalis with some small spines, and a larger, oblique, curved horn.

_Dimensions._--Length of the shell (with six joints) 0.2; length of the sixth joint 0.04, breadth 0.2.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

Subgenus 4. _Botryostrobus_, Haeckel.

_Definition._--Shell conical, with straight axis, joints of different lengths. Cephalis lobate, with some irregular constrictions. (Perhaps derived from #Botryodea#?).

23. _Lithostrobus botryocyrtis_, n. sp. (Pl. 79, figs. 18, 19).

Shell slender, conical, smooth, with straight axis, and three deep strictures. Joints of different lengths. The length of the fourth joint equals two-thirds of its breadth, and of the length of the three preceding joints together. Each of the latter bears three transverse rows of small, quadrangular pores, the fourth joint has six rows. The cephalis is irregularly lobate, with four to six prominent lobes, and two small divergent horns (fig. 19).

_Dimensions._--Length of the shell (with four joints) 0.1; length of the fourth joint 0.04, breadth 0.06.

_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.

24. _Lithostrobus lithobotrys_, n. sp. (Pl. 79, fig. 17).

Shell slender, conical, smooth, with straight axis, and four deep strictures. Joints of different lengths, gradually increasing towards the mouth, the length of the fifth joint equals half its breadth, and one-third of the length of the whole shell. The single joints bear each four or five transverse rows of small, roundish pores. Cephalis irregularly lobate, with four to six prominent lobes, and the same number of small, conical horns.

{1476}_Dimensions._--Length of the shell (with five joints) 0.12; length of the fifth joint 0.04, breadth 0.08.

_Habitat._--Central Pacific, Station 268, depth 2900 fathoms.

Genus 643. _Dictyomitra_,[260] Zittel, 1876, Zeitschr. d. deutsch. geol. Gesellsch., p. 80.

_Definition._--#Stichocorida# (vel Stichocyrtida eradiata aperta), with conical shell gradually dilated towards the wide open mouth. Cephalis without horn.

The genus _Dictyomitra_ agrees with the preceding _Lithostrobus_ in the slender, conical form of the multiarticulate shell, but differs from it in the absence of a horn on the cephalis; the horn is here completely lost.

Subgenus 1. _Dictyomitrella_, Haeckel.

_Definition._--Shell smooth, with joints nearly equal in length.

1. _Dictyomitra articulata_, Haeckel.

_Eucyrtidium articulatum_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, Taf. xi. figs. 2, 3.

Shell slender, conical, smooth, with six to eight deep strictures. All joints nearly equal in length, gradually increasing in breadth, the eighth four times as broad as long, and twice as broad as the fourth joint. In each joint three to four transverse series of small, regular, circular pores.

_Dimensions._--Length of the shell (with eight joints) 0.12, of each joint 0.015; breadth of the fourth joint 0.04, of the eighth joint 0.08.

_Habitat._--Fossil in Barbados.

2. _Dictyomitra macilenta_, Haeckel.

_Eucyrtidium macilentum_, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 291, Taf. vii. fig. 15.

Shell slender, conical, smooth, with five to seven deep strictures. All joints nearly equal in length, gradually increasing in breadth, the sixth joint three times as broad as long, and twice as broad as the second. In each joint only two transverse series of small, regular, circular pores.

_Dimensions._--Length of the shell (with seven joints) 0.08, of each joint 0.012; breadth of the sixth joint 0.036, of the second 0.018.

_Habitat._--Western Tropical Pacific, Stations 200 to 225, in various depths.

{1477}3. _Dictyomitra conica_, n. sp.

Shell widely conical, with six to eight prominent strictures. All joints nearly equal in length, gradually increasing in breadth, the eighth five times as broad as long, and twice as broad as the third. In each joint three to four transverse rows of regular, hexagonal pores. (Similar to _Lithostrobus hexagonalis_, Pl. 79, fig. 20, but more slender, and without cephalic horn.)

_Dimensions._--Length of the shell (with seven joints) 0.16, of each joint 0.022; breadth of the sixth 0.08.

_Habitat._--South Pacific, Station 295, depth 1500 fathoms.

Subgenus 2. _Dictyomitrissa_, Haeckel.

_Definition._--Shell smooth, with joints of very different lengths.

4. _Dictyomitra polypora_, Zittel.

_Dictyomitra polypora_, Zittel, 1876, Zeitschr. d. deutsch. geol.
Gesellsch., p. 80, Taf. ii. fig. 1.

Shell slender, conical, rough, with six to nine deep strictures. Breadth and length of the joints gradually increasing, so that the eighth joint is twice as long and broad as the third. Pores regular, circular, in transverse rows, four rows in each joint, in the last joint five to six rows.

_Dimensions._--Length of the shell (with eight joints) 0.24; length of the eighth joint 0.04, breadth 0.1; length of the third joint 0.02, breadth 0.05.

_Habitat._--Fossil in secondary rocks of Northern Germany (chalk of Brunswick, &c.), Zittel.

5. _Dictyomitra eurythorax_, n. sp. (Pl. 77, fig. 4).

_Lithocampium eurythorax_, Haeckel, 1881, Prodromus, p. 437, et Atlas,
pl. lxxvii. fig. 4.

Shell campanulate, conical, rough, with three deep strictures. Cephalis small, hemispherical. Thorax large, inflated, hemispherical, with six transverse rows of pores. Abdomen with two broader joints, together as long as the thorax, each with three to four rows of pores.

_Dimensions._--Length of the shell (with four joints) 0.14, of the thorax 0.06; breadth of the thorax 0.08, of the last joint 0.1.

_Habitat._--Central Pacific, Station 266, depth 2750 fathoms.

6. _Dictyomitra microcephala_, Haeckel.

_Eucyrtidium microcephalum_, Ehrenberg, 1858, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 32; Abhandl. d. k. Akad. d. Wiss. Berlin, 1872,
p. 291, Taf. xi. fig. 24.

Shell broadly conical, smooth, with six to eight distinct strictures. Breadth of the joints gradually increasing, length unequal. The three first joints short, only one-half or one-third as long as {1478}each of the following joints; in each of the former three to four transverse rows, in each of the latter six to eight transverse rows of small, regular, circular pores.

_Dimensions._--Length of the shell (with six joints) 0.09, of the three first joints 0.03, of the three following 0.06; breadth of the sixth joint 0.08, of the fourth 0.04.

_Habitat._--Mediterranean (Candia) Spratt, depth 1620 fathoms.

7. _Dictyomitra demersissima_, Haeckel.

_Eucyrtidium demersissimum_, Ehrenberg, 1872, Abhandl. d. k. Akad. d.
Wiss. Berlin, p. 291, Taf. vii. fig. 11.

Shell slender, conical, smooth, with four internal septal rings (without external strictures). Breadth of the five joints gradually increasing, length unequal; the third joint the longest, twice as long as the second, and longer than any of the following. Pores very small and numerous, in longitudinal rows.

_Dimensions._--Length of the shell (with five joints) 0.09, of the second joint 0.015, of the third 0.03; breadth of the second joint 0.03, of the third 0.05.

_Habitat._--Tropical Pacific, Philippine Sea, depth 3300 fathoms.

Subgenus 3. _Dictyomitroma_, Haeckel.

_Definition._--Shell with longitudinal ribs and furrows between them, with joints of different lengths.

8. _Dictyomitra costata_, n. sp.

Shell slender, conical, with prominent longitudinal ribs, and six to eight deep strictures. Length of the majority of joints nearly equal, the two or three first joints shorter, the last a little longer. In each joint only a single transverse series of pores at the distal end (one pore in each furrow). (Similar to _Siphocampe tubulosa_, Pl. 79, fig. 13, but conical, and without cephalic tube.)

_Dimensions._--Length of the shell (with eight joints) 0.16, of each middle joint 0.03, of the first 0.02; breadth of the last joint 0.06.

_Habitat._--Central Pacific, Station 295, depth 1500 fathoms.

9. _Dictyomitra multicostata_, Zittel.

_Dictyomitra multicostata_, Zittel, 1876, Zeitschr. d. deutsch. geol.
Gesellsch., p. 81, Taf. ii. figs. 2-4.

Shell slender, conical, with prominent longitudinal ribs, and eight to ten deep strictures. Length and breadth of the joints gradually increasing, the eighth joint twice as long and broad as the fourth joint. Pores regular, circular, one series in each longitudinal furrow, three to four pores on each joint.

{1479}_Dimensions._--Length of the shell (with eight joints) 0.2, of the fourth joint 0.02, of the eighth joint 0.04; breadth of the fourth joint 0.04, of the eighth 0.08.

_Habitat._--Fossil in secondary rocks of North Germany (chalk of Brunswick, &c.), Zittel.

Genus 644. _Stichocorys_,[261] Haeckel, 1881, Prodromus, p. 438 (_sensu emendato_).

_Definition._--#Stichocorida# (vel Stichocyrtida eradiata aperta) with a middle constriction of the shell, the upper half of which is conical, the lower cylindrical. Mouth truncate. Cephalis with a horn.

The genus _Stichocorys_ is intermediate between the two preceding and the two following genera; the upper half of the shell with the three first joints is conical, the lower half with the fourth and the following joints cylindrical, of equal breadth. The third joint of the shell (or the abdomen of _Theoconus_) is constantly the largest, being broader than all the other joints. _Stichocorys_ is a very common and characteristic form, and may be derived from _Theoconus_ by development of a post-abdomen.

1. _Stichocorys wolffii_, n. sp. (Pl. 80, fig. 10).

Shell in the upper half (with three joints) thorny, in the lower half (with two joints) smooth. Pores of the former double-contoured, in subregular, transverse rows. Pores of the latter smaller, simple, scarcely scattered. Cephalis with a pyramidal horn of the same length. Thorax with prominent, longitudinal divergent ribs. Dedicated to Caspar Friedrich Wolff (Halle, 1759).

_Dimensions._--Length of the shell (with five joints) 0.16; breadth of the third joint 0.08, of the fourth 0.05.

_Habitat._--Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. _Stichocorys panderi_, n. sp. (Pl. 80, fig. 7).

Shell in the upper conical half (with three joints) spiny, in the lower subcylindrical half (with three joints) smooth. Pores small, circular, irregularly scattered, simple. Cephalis with a conical horn of the same length. No longitudinal ribs. Dedicated to Christian Pander (Würzburg, 1817.)

_Dimensions._--Length of the shell (with six joints) 0.18; breadth of the third joint 0.08, of the fourth 0.05.

_Habitat._--Central Pacific, Station 265, depth 2900 fathoms.

3. _Stichocorys baerii_, n. sp. (Pl. 80, fig. 8).

Shell in the upper conical half (with three joints) spiny, in the lower cylindrical half (with three joints) sulcate, with prominent longitudinal ribs, alternating with longitudinal rows of small pores. {1480}Pores of the upper half smaller, quincuncially disposed. Cephalis with a stout pyramidal horn of the same length. Dedicated to Carl Ernst Baer (Königsberg, 1828).

_Dimensions._--Length of the shell (with six joints) 0.2; breadth of the third joint 0.09, of the fourth 0.07.

_Habitat._--North Pacific, Station 244, depth 2900 fathoms.

4. _Stichocorys okenii_, n. sp. (Pl. 80, fig. 5).

Shell smooth, without spines or ribs; the upper conical half (with three joints) about the same length as the lower subcylindrical half (with three joints). Pores subregular, circular, in the inflated third joint twice as large as in the five other joints. At the lumbar stricture (between the second and third joints) a coronal of nine very large pores. Cephalis with a curved horn of half the length. Dedicated to Lorenz Oken (Jena, 1806).

_Dimensions._--Length of the shell (with six joints) 0.2; breadth of the third joint 0.09, of the fourth 0.07.

_Habitat._--Central Pacific, Station 272, depth 2600 fathoms.

5. _Stichocorys huschkei_, n. sp. (Pl. 80, fig. 3).

Shell in the upper conical half (with three joints) thorny, in the lower cylindrical half (with five joints) smooth, roundish. Pores irregularly scattered, always double-contoured, in the second joint three times as large as in the third. At the third stricture (between the third and fourth joints) a coronal of larger pores. Cephalis with a small, conical horn of half the length. No longitudinal ribs. Dedicated to Emil Huschke (Jena, 1832).

_Dimensions._--Length of the shell (with eight joints) 0.18; breadth of the third joint 0.08, of the fourth joint 0.07.

_Habitat._--South Pacific, Station 285, depth 2375 fathoms.

6. _Stichocorys rathkei_, n. sp.

Shell spiny, everywhere covered with short conical spines. The upper conical part of the shell (with three joints) half as long as the lower cylindrical part (with six joints). Pores irregular, roundish, in the thorax twice to three times as large as in the eight other joints. Cephalis with a pyramidal horn of the same length. No longitudinal ribs. Dedicated to Heinrich Rathke (Königsberg, 1839).

_Dimensions._--Length of the shell (with nine joints) 0.24; breadth of the third joint 0.08, of the fourth joint 0.06.

_Habitat._--North Pacific, Station 253, depth 3125 fathoms.

7. _Stichocorys mülleri_, n. sp.

Shell in the upper conical part (with three joints) spiny, in the lower cylindrical part (with seven joints) smooth. Pores in the former irregularly scattered, roundish, in the latter circular, {1481}regularly disposed in longitudinal series, alternate, with prominent ribs. The upper conical part of the shell is about half as long as the lower cylindrical part. Cephalis with a large, pyramidal horn of three times the length. Dedicated to Johannes Müller (Berlin, 1858).

_Dimensions._--Length of the shell (with ten joints) 0.22; breadth of the third joint 0.09, of the fourth joint 0.06.

_Habitat._--Central Pacific, Station 268, depth 2900 fathoms.

Genus 645. _Artostrobus_,[262] n. gen.

_Definition._--#Stichocorida# (vel Stichocyrtida eradiata aperta) with cylindrical shell, the upper pole of which is rounded, the lower truncate. Cephalis with a horn.

The genus _Artostrobus_ and the following _Dictyomitra_ differ from all the other Stichocorida in the cylindrical or nearly cylindrical form of the shell, all the joints of which are nearly equal in breadth, and are very short, often with a single transverse row of pores only. The first joint or cephalis is usually different from the following, often hemispherical or cap-shaped joints. The last joint is truncate, and has a wide open mouth. Since the constrictions between the single joints are often very slight, some species are very similar to the Dicyrtide _Sethocorys_.

Subgenus 1. _Artostrobulus_, Haeckel.

_Definition._--A single transverse row of small, circular pores on each joint. (Sometimes on the uppermost joints two or three rows.)

1. _Artostrobus annulatus_, Haeckel.

_Cornutella annulata_, Bailey, 1856, Amer. Journ. Sci. and Arts, vol.
xxii. pl. i. fig. 5_a_, 5_b_.

_Eucyrtidium annulatum_, Haeckel, 1862, Monogr. d. Radiol., p. 327.

Shell slender, cylindrical, smooth, without external strictures, but with ten to twenty internal annular septa. On each joint only a single transverse row of small pores. Cephalis hemispherical, with a single or double small horn. Each joint about four times as broad as long.

_Dimensions._--Length of the shell (with twenty joints) 0.2; length of each joint 0.01, breadth 0.04.

_Habitat._--Arctic Ocean, Kamtschatka (Bailey); Greenland (Ehrenberg).

{1482}2. _Artostrobus elegans_, Haeckel.

? _Eucyrtidium elegans_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 70, pl. xi. fig. 12.

? _Eucyrtidium pauperum_, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss.
Berlin, p. 72, pl. xi. fig. 13.

Shell cylindrical, smooth, with eight to ten internal annular septa. Cephalis subspherical, with a short, conical horn. Thorax campanulate, with two transverse rows of pores. Abdomen with six to eight equal joints, each with a single row of pores. (May be described, perhaps, better as _Theocyrtis elegans_. _Eucyrtidium pauperum_, Ehrenberg, _loc. cit._, may be a variety of this species.)

_Dimensions._--Length of the shell (with nine joints) 0.1; length of each abdominal joint 0.01, breadth 0.03.

_Habitat._--Fossil in Barbados.

Subgenus 2. _Artostrobium_, Haeckel.

_Definition._--All (or the majority) of the joints of the shell with several transverse rows of pores, in variable number.

3. _Artostrobus auritus_, Haeckel.

_Lithocampe aurita_, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d.
Wiss. Berlin, p. 84.

_Lithocampe auricula_, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d.
Wiss. Berlin, p. 71.

_Eucyrtidium auritum_, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 25.

_Eucyrtidium auritum_, Stöhr, 1880, Palæontogr., vol. xxvi. p. 104, Taf.
iv. fig. 7.

Shell subcylindrical, with five sharp strictures. All six joints nearly equal in length; each with four or five transverse rows of small pores. Cephalis small, flat, hemispherical, with two or three small, conical, oblique horns. Mouth of the sixth joint a little constricted.

_Dimensions._--Length of the shell (with six joints) 0.12; length of each joint (on an average) 0.02, breadth 0.04 to 0.05.

_Habitat._--Fossil in Tertiary rocks of Sicily (Grotte, Caltanisetta).

4. _Artostrobus biseriatus_, n. sp.

Shell cylindrical, smooth, with ten to twelve deep strictures. All joints nearly equal in size; each with two transverse rows of small circular pores. Cephalis hemispherical, with a long, bristle-shaped, curved horn.