Chapter XV: Appendix: 4 (1)

ACCOUNT OF THE POLYZOA AND SERTULARIAN ZOOPHYTES, COLLECTED IN THE VOYAGE OF H.M.S. RATTLESNAKE, ON THE COASTS OF AUSTRALIA AND THE LOUISIADE ARCHIPELAGO, ETC. BY GEORGE BUSK, ESQUIRE F.R.S.

This collection includes about eighty-five species, distributed in twenty-nine genera, and may perhaps be regarded as the largest and most interesting of the kind ever brought to this country.

When it is stated that seventy-eight of the species are new or undescribed, the number will appear extraordinarily great, but when the comparatively neglected state of exotic Zoophytology is considered the wonder will be much diminished, and still further, as it may safely be assumed, that many of the species here given as new have been previously noticed, though so insufficiently described, as in the absence of figures not to admit of correct identification.

Making, however, a considerable deduction on this account, the remainder will still stamp the present collection with extreme value. As an instance, may be cited the genus Catenicella, of which this collection affords about fifteen species, and of which certainly not more than three have been previously noticed in any way, and of these no sufficient descriptions or figures are extant by which even that small number could be identified. The explanation of this is perhaps to be sought in the circumstance that the species of Catenicella are deepsea forms, and only to be obtained by dredging in deep water--very few being apparently found on the shores.

Though the number of new or supposed new species is so great, the number of new genera is comparatively small, not amounting to more than four. It has, however, been found necessary considerably to modify the characters of several other established genera, so as to include new species.

With respect to the geographical distribution of the species, my means of comparison have been pretty extensive. They have been derived from the examination of Mr. Darwin's and Dr. Hooker's collections, placed at my disposal by the kind liberality of Mr. Darwin--a considerable collection of South African species mainly procured from Mr. Bowerbank--and from the Collection of British and exotic Zoophytes in the British Museum, for the freest opportunities of examining which I have to thank Mr. Gray. From these various sources, and others of less account, I have been able to examine species from a very considerable extent of the earth's surface--more especially in the Southern hemisphere, and to arrive perhaps at as fair a view of the geographical distribution of species as the present imperfect state of Zoophytology will allow.

...

POLYZOA.

The number of species of Polyzoa is about fifty-four--belonging to twenty-four genera. Of these genera it is believed that four will be found to be new, or hitherto undescribed, and it has been deemed requisite to modify the characters of several others upon the more extended survey of species afforded mainly by the present collection. The new genera here instituted are:

Calpidium. Diachoris. Didymia. Dimetopia.

And the genera whose characters it has been found requisite to modify are:

Catenicella. Salicornaria. Cellularia. Scrupocellaria. Bicellaria. Canda. Emma. Acamarchis. Caberea.

Of the twenty-four genera, three, or perhaps four, appear to be peculiar to the Australian seas. These are:

Calpidium. Canda ? Didymia. Dimetopia.

All the rest, excepting two, Emma and Diachoris, appear to be distributed over the globe in both hemispheres. The above two are perhaps limited to the southern.

Of the fifty-three species, about thirty-three seem to be new, or to have been so imperfectly described as not to admit of precise identification, and five others have synonyms more or less doubtful applied to them.

Six species only are common to the seas of Europe, namely:

Tubulipora phalangea ? Crisia denticulata. Eucratea chelata. Anguinaria spatulata. Acamarchis neritina. Retepora cellulosa.

Sixteen others are met with in other parts of the Southern hemisphere, namely:

Catenicella elegans ? Catenicella ventricosa. Eschara lichenoides, occurring in Algoa Bay. Caberea zelanica. Acamarchis tridentata, in Algoa Bay and New Zealand. Caberea lata. Catenicella hastata. Catenicella cribraria. Catenicella cornuta. Cellularia monotrypa. Bicellaria tuba, in New Zealand and Emma crystallina. Emma tricellata, in New Zealand and Campbell's Island.

Thus of the fifty-four species, about thirty-four would seem to be peculiar to the Australian seas. Ten of these belong to the genus Catenicella, and one to the closely-allied Calpidium, three to Didymia and Dimetopia, and one to Diachoris, of which genus two other species are found in the Straits of Magellan.

The method according to which the Polyzoa are arranged, is, in the primary divisions at least, pretty nearly identical with that indicated in the Synopsis of the Families and Genera of Polyzoa Infundibulata, given in Dr. Johnston's British Zoophytes.*

(*Footnote. Volume 1 page 263 2nd Edition.)

A few words, however, will be necessary to explain more particularly the subsequent subdivisions here adopted.

The order, Polyzoa infundibulata, is divided into three suborders, coinciding very nearly with the Tubuliporina, Celleporina, and Vesicularina of the work above referred to, but as the characters of these suborders are derived from the conformation of the opening of the cell, I have thought it more convenient to name them accordingly. The first suborder, having a round, simple opening to the cell, is here termed the Cyclostomata; the second, with the opening of the cell filled up by a usually thin, membranous or calcareous velum, and with a crescentic mouth provided with a movable lip, the Cheilostomata; and the third suborder, which might perhaps include the Halcyonellea of Ehrenberg, as well as the Vesiculariadae, distinguished by the existence of a more or less well-marked fringe of setae (sometimes only rudimentary) around the opening of the cell when the animal is protruded, the Ctenostomata.

The following synoptical arrangement--which it must be remarked, includes only the genera occurring in the Rattlesnake collection--will serve to indicate the subsequent divisions.

SYNOPTICAL ARRANGEMENT OF THE POLYZOA INCLUDED IN THE RATTLESNAKE COLLECTION.

Suborder 1. CYCLOSTOMATA (Tubuliporina).

Fam. 1. TUBULIPORIDAE. Gen. 1. Tubulipora. Sp. 1. T. phalangea ? 2. Pustulipora. 2. P. australis, n. sp. 3. Idmonea. 3. I. radians.

Fam. 2. CRISIADAE. 4. Crisia. 4. C. denticulata. 5. C. acropora, n. sp.

Suborder 2. CHEILOSTOMATA (Celleporina).

§. 1. UNISERIALARIA.

Fam. 1. CATENICELLIDAE. 5. Catenicella. a. fenestratae. 6. C. hastata, n. sp. ? 7. C. amphora, n. sp. 8. C. margaritacea, n. sp. 9. C. ventricosa, n. sp. 10. C. plagiostoma, n. sp. 11. C. lorica, n. sp. 12. C. cribaria, n. sp. b. vittatae. 13. C. formosa, n. sp. 14. C. gibbosa, n. sp. 15. C. elegans, n. sp. 16. C. cornuta, n. sp. 17. C. umbonata, n. sp. c. inermes. 18. C. carinata, n. sp. 6. Calpidium, n. g. 19. C. ornatum, n. sp.

Fam. 2. EUCRATIADAE. 7. Eucratea. 20. E. chelata. 8. Anguinaria. 21. A. spatulata.

§ 2. MULTISERIALARIA. 1. Articulata. a. internodes elongated, multicellular.

Fam. 1. SALICORNARIADAE. 9. Salicornaria. 22. S. punctata, n. sp. ? 23. S. bicornis, n. sp. 24. S. dichotoma, n. sp. 25. S. marginata, n. sp.

Fam. 2. CELLULARIADAE. 10. Cellularia. 26. C. monotrypa, n. sp. 11. Scrupocellaria. 27. S. cervicornis, n. sp. 28. S. diadema, n. sp. 29. S. cyclostoma, n. sp. 30. S. ferox, n. sp. 12. Canda. 31. C. arachnoides. b. internodes short, 2-4 celled. 13. Emma. 32. E. crystallina. 33. E. tricellata, n. sp.

2. Inarticulata.

Fam. 3. BICELLARIADAE. 14. Bicellaria. 1 34. B. tuba, n. sp. 35. B. gracilis, n. sp. 36. B. grandis, n. sp. 37. B. flexilis, n. sp. 15. Acamarchis. 38. A. neritina. 39. A. tridentata.

Fam. 4. CABEREADAE. 16. Caberea. 40. C. rudis, n. sp. 41. C. zelanica. 42. C. lata, n. sp. ?

Fam. 5. FLUSTRADAE. 17. Flustra. 43. F. pyriformis ? 44. F. denticulata, n. sp. 18. Retepora. 45. R. cornea, n. sp. ? 46. R. cellulosa. 47. R. ctenostoma, n. sp. 19. Eschara. 48. E. lichenoides. 20. Diachoris, n. g. 49. D. crotali, n. sp.

Fam. 6. CELLEPORIDAE. 21. Cellepora. 50. C. bilabiata, n. sp. ?

Fam. 7. GEMELLARIADAE. 22. Didymia, n. g. 51. D. simplex, n. sp. 23. Dimetopia, n. g. 52. D. spicata, n. sp. 53. D. cornuta, n. sp.

Suborder 3. CTENOSTOMATA. (Vesicularina, etc.)

Fam. 1. VESICULARIADAE. 24. Amathia. 54. A. biseriata.

Suborder 1. CYCLOSTOMATA.

Fam. 1. TUBULIPORIDAE.

1. TUBULIPORA, Lamarck.

1. T. phalangea, Couch. Habitat: Bass Strait, 45 fathoms.

A small, imperfect specimen, which may be referred to the variety noticed in British Zoophytes, and figured Plate 46, figures 3, 4.

2. PUSTULIPORA, Blainville.

1. P. australis, n. sp. P. deflexa ? Couch.

Branched dichotomously; branches short, incrassated, truncate. Cells wholly immersed, or about half free, numerous; surface minutely papillose, summits of papillae of a dark brown or black colour.

Habitat: Bass Strait, 45 fathoms; and elsewhere in the Australian seas.

About half an inch high. The stem becomes thicker as it ascends, and divides into two equal short branches, each of which again subdivides into two short truncate branches, in a plane at right angles to the primary division. The cells in the upper part of the stem appear free for nearly half their length, and are gently curved outwards. The surface is covered with pretty regularly and quincuncially arranged minute papillae, the apex of each of which is flattened or rounded, and of a dark brown or black colour. The mode of subdivision of the polyzoary, and the truncated ends of the branches, and the more numerous cells, suffice to distinguish this species from P. proboscidea. The cells in the figure of P. deflexa appear to be much more slender in proportion, and the branches in that species are not truncated, but attenuated at the extremity.

3. IDMONEA, Lamouroux.

1. I. radians, M. Edwards. Ann. de Sc. N. tome 9 page 25 plate 12 figure 4. Retepora radians, Lamarck. Habitat: Bass Strait, 45 fathoms.

One minute specimen, but very perfect, has been examined; but it is undoubtedly the one described and figured by M. Edwards, and noticed by Lamarck as inhabiting the seas of New Holland. M. Edwards' doubt therefore as to this locality is now removed.

Fam. 2. CRISIADAE.

4. CRISIA, Lamouroux.

1. C. denticulata, Fleming. Habitat: Bass Strait, 45 fathoms.

Parasitic upon a species of Salicornaria. The only difference, if there be any, between this form and the British, consists in the rather greater projection or freedom of the extremities of the cells, which are curved towards the front.

2. C. acropora, n. sp.

Cells 9 to 13 in each internode; lateral branches given off between the first and second, or between the second and third cells above a joint. A small conical tooth, sometimes bifid, above and behind the mouth.

Habitat: Bass Strait, 45 fathoms.

A small parasitic species, distinguished from C. denticulata, which it much resembles, by the less average number of cells in each internode, and the less number intervening between the origin of a branch and the joint below it, and by the small conical tooth or tubercle above and behind, or to the outer side of the mouth.

Suborder 2. CHEILOSTOMATA.

§ 1. Uniserialaria. Cells disposed in a simple series.

Fam. 1. CATENICELLIDAE. Cells connected by flexible joints.

5. CATENICELLA, M. Edwards (Lamarck An. s. Vert. tome 2 page 181.)

Cells arising one from the upper and back part of another by a short corneous tube, and disposed in a linear series, all facing the same way, and forming dichotomously divided branches of a phytoid polyzoary; cells geminate at the bifurcation of the branches; each cell furnished with two lateral processes usually supporting an avicularium. Ovicells either subglobose and terminal, or galeriform and placed below the mouth of a cell in front.

This interesting and important genus may be regarded as characteristic, not only of the present collection, but perhaps also of the Australian seas, as far as the Polyzoa are concerned. Thirteen species are here described, and as it has been found extremely difficult in most cases to identify any of them with the very few hitherto noticed forms, the synonyms given must be regarded as at least extremely doubtful.

Each cell arises from the upper and back part of another, with the intervention of a short corneous tube which is prolonged from the interior of one cell to that of the one above. The cell is furnished on each side at the top with a usually well-developed avicularium, in some species of huge size, and in some very minute, or entirely aborted. This avicularian process in most cases supports above a hollow process, which is sometimes closed and more or less elongated, constituting a conical or acerose spine, sometimes open above and assuming the form of a shallow cup or receptacle. In some species both modifications of this portion of the lateral process are met with in the same specimen. This form of spine or cup--as the case may be, is always distinctly separated by a septum from the cavity of the avicularium itself. Below the avicularium there is also in many cases a third distinct cavity which is usually widely open, the opening being covered in very frequently by a convex transparent membrane, and its bottom apparently perforated by several minute foramina--from this part of the lateral process there is in many species a prominent ala or keel prolonged to the bottom of the cell--which ala not unfrequently divides into two branches, which, again coalescing at the bottom of the cell, circumscribe a more or less oval space, the bottom of which is also perforated by minute foramina or apparent foramina, and which is often covered over by a transparent convex membrane. This membrane, however, as well as that which covers in the subavicularian space, is more usually broken off and wanting.

The inferior oval space above described is here termed the lateral area, and it is employed in the specific characters. It would thus be correct to say--that each cell is furnished with two lateral processes, each of which in the fully developed state consists of three distinct compartments--one superior, a cup or spine: a middle one, which is the avicularium: and an inferior; and it would appear that one or more of these elementary compartments of the lateral process may be more developed than the next, or sometimes entirely aborted. The mouth of the cell is situated at the upper part in front, and is of the same conformation as in the rest of the Cheilostomatous suborder. An important generic character consists in the gemination of the cell at each bifurcation.*

(*Footnote. Table 1 figures 1 and 2.)

These characters are common to all the species included in the genus, which furthermore admits of being subdivided into two extremely natural sections or subgenera (or perhaps into three). These subdivisions are named respectively the fenestratae, and the vittatae.

In the fenestrate division, in the whole of which the cells are of larger size and stronger than in the other, the wall of the cell appears to be constituted of at least two distinct laminae. The external lamina, on the front of the cell, is perforated by a certain number of holes, is wanting rather in a certain number of spaces, for which spaces the term fenestrae is employed. These apparent openings do not, therefore, penetrate into the cavity of the cell. But besides the fenestrae, there is, in some cases, a small central opening which does penetrate through the wall. In most cases the fenestrae are arranged in a crescentic, or rather horseshoe-shaped line, indicative, as it were, of the limits of a regular oval space, in the front wall of the cell, the upper part of which oval would be formed by the mouth, and the remainder filled up by the deposition of calcareous matter, as happens for instance in the older cells towards the bottom of the polyzoary in certain Cellulariae, etc.

A further characteristic of the fenestrate Catenicellae is the terminal position of the ovicells. These organs are clearly transformed cells, or cells dilated to considerably more than their natural bulk, and assuming a subglobose form. And what is worthy of remark, these terminal ovicells always have a sessile avicularium on the summit.

In the Vittatae the cell is smaller, and usually more delicate and transparent. They probably want the outer lamina, or have it very thin, and consequently present no fenestrate spaces, and the front of the cell is beset (sometimes very sparingly) with more or less prominent, minute, acuminate papillae. On each side, sometimes on the anterior aspect, sometimes quite laterally, is a narrow elongated band or vitta, as it is here designated, from which the distinctive sectional appellation is derived. This band or stripe varies in width and proportionate length and position in different species; it is slightly elevated, and marked with larger, or small circular discoid, or acuminated eminences. This subdivision is further distinguished by the situation of the ovicells, which are not terminal, but occur at irregular intervals on cells in the course of the series. They are of the same galeate form as in many others of the Escharinae, but are not as in them placed above the mouth of the cell, but below it in front: and in all cases the shape of the ovicell-bearing cell is much altered from the rest, and in all the vittate species the cell upon which the ovicell is produced arises from its predecessor, not with the intervention of a short tube, but is immediately sessile upon it, by a broad base.

a. Fenestratae.

Cells large, fenestrate in front; ovicells terminal.

1. C. hastata, n. sp. ?

C. bicuspis ? Gray. Dieffenbach's New Zealand, Volume 2 page 293.

Fenestrae, 7 to 9, disposed in a crescent, and with elongated fissures radiating towards them from the median line. Avicularia supporting a large pyramidal pointed hollow process, compressed, and perforated before and behind by five or six small circular pores.

Habitat: Bass Strait, 45 fathoms, dead shells.

Of a yellowish white colour, sometimes reddish. Forms fine bushy tufts, with long wavy branches, arising from a short common stem, and it attains a height of five or six inches. It appears sometimes to be parasitic upon other polyzoa, and is then much smaller. Its peculiar characteristics are the perforated and striated scutiform area on the front of the cell and the perforated, or apparently perforated pyramidal lateral processes above each avicularium; these processes are much developed, and give the cell the form of a broad inverted shear-head. It seems to be an abundant species in Bass Strait, and it occurs also in New Zealand. (Dr. Hooker's Collection.)

2. C. amphora, n. sp.

Cellaria catenulata ? var. B. Lamarck. Anim. sans Vert. Volume 2 page 180 2nd edition.

Cells oval, sides rendered straight upwards by the broad avicularia which are prolonged upwards into an acute spinous angle, and support a shallow cup. Front of cell with nine pyriform fenestrae, with fissures proceeding from their pointed ends towards an oval central perforation. An elevated band, extending from the sides of the mouth to the upper angular processes of the avicularia. An elevated flattened band along the middle of the back, which at the top sends off a narrower lateral band to each avicularian spine.

Habitat: Bass Strait, 45 fathoms.

A fine species of a bright reddish brown, and in the younger cells very transparent. Forms small, irregularly branched bushes, four to six inches high and wide. It is peculiar by its extremely regular vase-like form of cell, which is given by the continuation upwards of the broad avicularia in nearly a straight line, and their prolongation into a sharp angular spine, on the inner side of which is a shallow cup-like cavity, whose sides are usually more horny than calcareous. The number of fenestrae appears to be very constant.

The length of the branches before their dividing, and their straightness, together with the colour of this species, render it not improbable that it is the form intended by Lamarck (l.c.).

3. C. margaritacea, n. sp.

Cellaria vesiculosa ? Lamarck.

Cells oval or sub-globular, much compressed; avicularia short and broad, supporting a deep cup-like cavity. Fenestrae 5, large. Lower margin of mouth notched in the middle; back of cell minutely sulcated; sulci short, interrupted, and irregular. A small lateral area.

Habitat: Swan Island, Banks Strait.

A very beautiful species, the branches resembling strings of minute pearls. The pearly lustre (in the dry state) owing without doubt to the minute sulci on the backs of the cells. These sulci are not, however, consequent upon the drying, because they are equally apparent and constant when the specimen has been immersed in fluid. The species may almost at once be distinguished by the notch in the lower margin of the mouth, which notch represents the central suboral opening present in some other species.

4. C. ventricosa, n. sp. Table 1 figure 1.

Cells oval, compressed, rather wide below; avicularia wide, supporting sometimes a cup-like cavity, sometimes a closed broad conical spine. The prehensile part of the avicularium itself small, seated in a deep notch below the acuminate summit; lateral area large and well defined. Fenestrae 7, with fissures radiating to a rounded central opening. Anterior surface of cell studded with minute acuminate papillae; posterior surface smooth, sometimes spotted.

Habitat: Bass Strait, 45 fathoms.

Colour dirty white or brown. Habit stiff, stem strong, straight, branches short and crowded--probably attains a height of four or five inches. The only other species with which it can be confounded is C. amphora, from which it differs in the greater size and more irregular form of the lateral processes, in the presence of the minute papillae on the surface, and in the absence of the narrow longitudinal band on the back; instead of which the older cells in C. ventricosa exhibit a sort of broad scutum, almost covering the back of the cell and sending off two lateral bands on the sides of the cell, one passing below the avicularium and above the lateral area, and the other towards the acuminated apex of the avicularium. It also wants the raised bands which in C. amphora pass from the sides of the mouth to the apex of the avicularium in front. One large specimen presents a variety worthy of note--in this the backs of all the cells, except one here and there, exhibit (internally ?) numerous irregular-sized leopard-like spots.

5. C. plagiostoma, n. sp.

Cells short-ovoid; avicularia very large and long, ascending from near the bottom of the cell into an acute spinous point, and supporting a deep cupped cavity; mouth placed obliquely; front of cell divided into five large subtriangular fenestrae by four broad bands. Back of cell with a broad central band and two narrower bands branching from it on each side; surface of spaces left uncovered by the bands on the back beset with scattered, long setose spines.

Habitat: Bass Strait, 45 fathoms.

Colour brownish white; habit stiff, branches short. This species is at once recognisable by the peculiar oblique position of the mouth--the enormously developed avicularium usually only on one side of the cell, and by the sculpture of the cell--which appears as if it were swathed with broad tapes or bands. The wide spaces left between the bands in front clearly represent the true nature of the fenestrae of other species. It is the only species furnished with elongated setose spines.

6. C. lorica, n. sp.

Cellaria catenulata ? Lamarck.

Cells elongated rhomboidal, truncated at each end. Fenestrae three, large, the lowest the largest, arranged in a triangle. Mouth very large; avicularia wide and strong; two lateral areae on each side, well developed; surface in front with a few indistinct circular spots around the fenestrae, and behind marked with faint longitudinal striae.

Habitat: Bass Strait, 45 fathoms.

Colour white, transparent. A fine widely branching species, in which the catenulate aspect is more evident to the eye than in almost any other. It is at once recognisable by the rhomboidal scutate form of the cell viewed anteriorly, and, when the back is also viewed, the resemblance of the two aspects to the back, and breastplates of a coat of mail, is very striking. The structure of the lateral processes is more distinctly to be made out in this species than in any other. Each lateral process consists, first, of a deep cup-like cavity above; second, a middle compartment, the avicularium; and third, a third loculament below the avicularium, the wide opening of which is covered in by a convex transparent membrane. The bottom of this loculament appears to be perforated, and it is to be noticed also that there is a small central perforation in the septum separating it from the cavity of the avicularium. Towards the bottom of the cell, on each side, is a well developed lateral area of exactly the same conformation as the sub-avicularian loculament, and like it covered in by a convex transparent membrane. It might be supposed that these cavities were for the purpose of containing air, in order to render the otherwise heavy branches of the polyzoary buoyant. They, at all events, appear to be perfectly empty.

7. C. cribaria, n. sp.

Cells sub-globular, compressed, more or less alate. Avicularia large, without any superior appendage, and prolonged downwards into elevated lateral alae. Anterior surface with numerous small round fenestrae, placed at equal distances apart, and evenly distributed over the surface, the circumferential fenestrae being larger than the rest. A minute central perforation of a crescentic form, the lower lip projecting, and the upper lip, lingulate in the middle, falling behind the lower.

Habitat: Bass Strait? This species also occurs in New Zealand.

Colour brown, loosely branched and several inches high. Distinguished readily by the cribriform aspect of the front of the cell, and by the curiously formed central orifice, and by the absence of any superior appendage to the avicularium.

b. Vittatae.

Cells furnished with a narrow elongated band or vitta on each side, without fenestrae. Ovicells not terminal, galeriform.

8. C. formosa, n. sp.

Cells oval; avicularia large, flat, or cupped above. Vittae elliptical, rather anterior.

Habitat: Swan Island, Banks Strait.

Colour light plumbeous. Parasitic upon C. margaritacea. The cells are the largest of any in the Vittate division, and very regular and uniform in size and outline. The more distinctive characters are taken from the comparatively broad vittae, and the flat or cupped upper surface of the avicularia, which are usually continued downwards into a prominent ridge or ala.

9. C. gibbosa, n. sp.

Cells pyriform, ventricose posteriorly, much attenuated at bottom. Avicularia small, placed in front close to the sides of the mouth, at the base of strong conical pointed processes which project in front, and are connected across the top of the cell by a prominent toothed ridge. Vittae long linear, entirely lateral.

Habitat: Prince of Wales Channel, Torres Strait, 9 fathoms, mud.

Of a dark lead colour, when dry. Forms an elegantly branched bush about two inches high. The gibbous form of the cells, and the peculiar anterior position of the avicularia, at the base of the projecting lateral processes, at once distinguish it from all the other vittate species. The toothed (sometimes entire) ridge extending between the two lateral processes across the top of the cell and overlapping the mouth like a penthouse is also a very peculiar feature.

10. C. elegans, n. sp. Table 1 figure 2.

Cells elongated ovoid; avicularia large and projecting, without any superior appendage; vittae narrow, rather anterior.

Habitat: Bass Strait, 48 fathoms. Port Dalrymple, on stones at low water.

A delicate and beautiful parasitic species; the branches slender and spreading; colour white and very transparent. Cells regular and uniform in size and shape. A very similar if not identical species occurs in Algoa Bay, South Africa, the only difference between them being that the latter is rather larger and has the vittae much longer; in the Australian forms these bands do not reach above the middle of the cell, whilst in the South African they extend as high as the mouth.

11. C. cornuta, n. sp.

Cells oval; avicularia in many cells wholly transformed into long pointed retrocedent spines, on one or both sides, in others into shorter spines or unaltered. Vittae linear, extremely narrow, entirely lateral, and extending the whole length of the cell from the base of the avicularium.

Habitat: Bass Strait, 45 fathoms.

Colour yellowish white, growth small; parasitic upon C. amphora. As some difficulty might be experienced in the discrimination of this species from C. elegans, and another South African species (not the variety of C. elegans above noticed) it is requisite to remark that the long retrocedent spines when present are not placed upon or superadded to the avicularia, but that they seem to represent an aborted or transformed state of those organs. They vary much in length and size in different cells, and even in those of the same branch; as it frequently happens that there is a spine, usually of diminutive size, on one side and a very large avicularium on the other, and sometimes (but rarely) an avicularium of more moderate size on both sides. But the character of the species by which it is more particularly distinguished consists in the presence on a great many cells, in one part or other of the polyzoary, of the two large and strong spines projecting BACKWARDS. This retrocession of the spines is alone a sufficient character to distinguish the present species from the South African form above alluded to (C. taurina, B.) And the length and lateral position of the vittae would distinguish the unarmed cells from those of C. elegans.

12. C. umbonata, n. sp.

Cells more or less pyriform, alate, narrow below, bulging or ventricose upwards. Avicularia large and strong. Vittae strap-shaped, anterior, extending from the level of the mouth to the bottom of the cell, with elevated acuminate papillae or short spines. A broad compressed projecting process on the middle of the back.

Habitat: Bass Strait, 45 fathoms.

The cells in this species are small, inflated or ventricose, and as it were sub-globular above, becoming much attenuated below--but the cavity of the cell does not appear to extend into this contracted portion, in which is contained the connecting tube strengthened by calcareous matter--the inferior continuation of the lateral alae, which descend from the base of the avicularium. Owing to the large size of the avicularia, the upper part of the cell is much widened, and the whole acquires somewhat of a triangular form, and has a peculiar rugose aspect, derived, in part also, from the large size and elevation of the acuminated papillae, not only of the vittae but on the surface of the cell itself. The central umbo or crest posteriorly is a marked feature.

c. Without vittae or fenestrae.

13. C. carinata, n. sp.

Cells oval, narrowed at both ends; lateral processes (without avicularia ?) projecting horizontally upwards from the sides of the mouth about the middle of the cell. Mouth nearly central, with a small tooth on each side, and below it a triangular space with three strong conical eminences. The cell which bears the ovicell geminate.

Habitat: Bass Strait, 45 fathoms.

This remarkable form differs so widely in many respects from any of its congeners, as almost to deserve to be considered as the type of a distinct sub-genus. The lateral processes, which may be taken to represent the perfect avicularia of the other species, are, as far as can be ascertained from specimens that have been dried, without a movable mandible, and are probably really so, because there is no corresponding beak. These processes are channelled in front, nearly from the base to the extremity; they arise by a broad base on each side of the mouth, and on the front of the cell, and from the conjoined bases is continued upwards and downwards, or to the top and bottom of the cell, a prominent flattened band. The expanded bases circumscribe an oval space, nearly in the centre of the front of the cell, the upper two-thirds of which space are occupied by the circular mouth, on each side of which is a small calcareous tooth, to which apparently are articulated the horns of the semilunar lateral cartilage. The lower third is filled up by a yellow, horny (?) membrane, upon which are placed three conical eminences, disposed in a triangular manner. The back of the cell is very convex, and has running along the middle of it an elevated crest or keel, which is acuminate in the middle. The ovicell is situated in front of the cell below the mouth, and below it are three considerable-sized areolated spots, disposed, like the three conical spines, in a triangle. The cells upon which the ovicells are placed are always geminate, that is to say, have a smaller cell growing out from one side.

6. Calpidium, n. gen. Table 1 figures 3 to 5.

Character: Cells with an avicularium on each side; with two or three distinct mouths, arising one from the upper part of another, in a linear series, all facing the same way, and forming dichotomously-divided branches; cells at the bifurcation single; ovicells ---- ?

This very peculiar genus, remarkable as it is, seems hitherto to have escaped notice. It is distinguishable from Catenicella, in the first place, by the anomalous circumstance that each cell is furnished with two or more, usually three, distinct keyhole-shaped mouths, and is doubtless inhabited by three distinct individuals. Whether these are separated from each other by internal partitions is unknown, but the closest examination of cells rendered transparent by means of acid fails to discover such. In cells thus prepared, there are apparent, however, three distinct masses, reaching from the bottom of the cell to each orifice, and which are probably the remains either of the body or of the retractor muscles of the animals. Another point of difference from Catenicella is the non-gemination of the cell at the dichotomy of a branch. The avicularia, moreover, do not form lateral projections, but are sessile, or imbedded, as it were, in the sides of the cell immediately below the upper angles.

1. C. ornatum, n. sp. Table 1 figures 3 to 5.

Cells triangular-urn shaped, very broad above, with a straight border, much compressed; mouths, 2 to 3, keyhole-shaped. Five fenestrae below each mouth; numerous branching bands on the back of the cell.

Habitat: Bass Strait, 45 fathoms.

This curious species is the only one belonging to the genus. The cells are very large, regular, and uniform, resembling very closely an antique sculptured urn. Colour dark brown, and the walls so thick as to be nearly opaque. The polyzoary, which appears to attain a height of four or five inches, is bipinnate (with all the branches on one plane) the branches alternate, and given off with extreme regularity. The ultimate ramules are incurved. The whole forms a very elegant object. The central stem, or series of cells, differs in no respect as regards the size or disposition of the cells composing it, from the branches.

Fam. 2. EUCRATIADAE.

7. EUCRATEA, Lamouroux.

1. Eucratea chelata, Lamouroux.

Habitat: Bass Strait, 45 fathoms.

In all respects identical with the British form. It also occurs at Port Adelaide.

8. ANGUINARIA, Lamarck.

1. A. spatulata, Lamarck.

Aetea anguina, Lamouroux.

Habitat: Bass Strait, and other localities.

This species (which appears to be pretty generally distributed over the globe) is identical with the European form. It is to be remarked, however, that a second species (A. dilatata, Busk. Annals of Natural History second series volume 7 page 81 plate 9 figure 14) is found in Torres Strait, but which does not occur in the Rattlesnake collection.

...

§ 2. MULTISERIALARIA. Cells disposed alternately in a double or multiple series.

1. Articulata.

Polyzoary divided into distinct internodes by flexible articulations.

a. Internodes elongated, or composed of numerous cells.

Fam. 1. SALICORNARIADAE. Cells disposed around an ideal axis.

9. SALICORNARIA, Cuvier.

a. Surface divided into more or less regular hexagonal spaces by elevated ridges.

1. S. punctata, n. sp.

Cellaria salicornioides ? Audoin. Savigny, Egypt. Plate 6 figure 7.

Hexagonal areas with an acute angle above and below; bottom of area pyriform, surface covered with minute transparent granulations. Mouth of cell in the upper third, with a minute tooth on each side.

Habitat: Bass Strait, 45 fathoms. Off Cumberland Islands, 27 fathoms, fine grey mud.

Parasitic upon Sertularians and Polyzoa; branches straggling of irregular lengths.

2. S. bicornis, n. sp.

Areas with an obtuse angle above and below, sometimes rounded above; a minute projection on each side near the top. Bottom of area long-oval, smooth, sometimes with a perforation above the mouth. Mouth with a minute tooth on each side.

Habitat: Bass Strait, 45 fathoms.

Parasitic. Branches shorter and thicker than in the preceding species. In the shape of the area they are very much alike, but in S. bicornis, in some cells, and occasionally throughout the greater part of the internode, the area differs widely from the more usual form. It is much expanded, and presents a wide arch above. In this case there is usually a considerable-sized perforation above the mouth of the cell, as occurs not infrequently also in S. farciminoides in the younger cells, and which opening is probably normal, until it becomes filled up by the gradual disposition of calcareous matter. What more especially distinguishes the present from the preceding species are the minute projections on either side at the two upper lateral angles of the hexagonal area, and the smoothness of the surface of the cell. They are both perfectly distinct from S. farciminoides.

b. Surface not divided into distinct areas by raised ridges.

3. S. furcata, n. sp.

Mouth of cell elliptical, occupying two-thirds of its length. Two small perforations on each side immediately above the mouth, protected by a convex transparent hood, which has a rounded opening on its under surface.

Habitat: Prince of Wales Channel, Torres Strait, nine fathoms.

Forms small crowded tufts from one to two or three inches high; branches very regularly dichotomous.

4. S. torresiana, n. sp.

Cell circumscribed by an acute raised border; opening oval, rather more than half the length of the cell. Cell attenuated below the opening.

Habitat: Prince of Wales Channel, Torres Strait, nine fathoms.

A small broken fragment only preserved; parasitic upon Sertularia mutulata, so that its habit cannot be satisfactorily determined. It is of a greenish colour, but this may be adventitious, although general and uniform throughout the specimen. This species differs from the above in being much larger, and in wanting the two perforations on each side above the mouth--in the less comparative size of the opening of the cell, and in the remarkable elevation of the sharp margin surrounding the upper half of the cell. In the looser aggregation, and in the form of the cells, it shows the transition from Salicornaria to Cellularia.

Fam. 2. CELLULARIADAE. Cells disposed in the same plane.

10. CELLULARIA, Pallas.

Character: (B.) Cells bi-triserial, oblong* or rhomboidal, contiguous. Opening of cell occupying at least half of the front. Margin thickened, sometimes spinous above. A short spine or a sessile avicularium on the upper and outer angle.

(*Footnote. This shape of the cells is given from the back view of them.)

A. inarmatae--without avicularium.

1. C. monotrypa, n. sp.

Cells oblong, narrowed below, with a single perforation, in the upper and outer part behind. Opening oval, margin smooth; a short spinous process at the upper and outer angle; a sharp short spine in the middle of the upper border of the middle cell, at a bifurcation. Ovicell ? in form of a very shallow excavation in the upper part of the cell in front.

Habitat: Bass Strait, 45 fathoms.

The only species with which this can be confounded, is C. peachii (Busk. Annals of Natural History volume 7 second series page 82 plate 8 figure 1.)

The latter, however, is very much smaller, the cells narrower in proportion to their length, and the margin of the opening minutely verrucose. The cell has more than one posterior perforation; and the central cell at a bifurcation is rounded above and without a spinous process; lastly, the ovicell is much loftier and tesselated on the surface.

11. SCRUPOCELLARIA, Van Beneden.

Character (modified). Cells rhomboidal, with a sinuous depression on the outer and posterior aspect. Each furnished with a sessile avicularium at the upper and outer angle in front, and with a vibraculum placed in the sinus on the outer and lower part of the cell behind. Opening oval, or subrotund, spinous above. Ovicells galeriform.

This natural genus is characterised more particularly by the presence upon EACH cell of a sessile avicularium seated on, or in fact forming the upper and outer angle, and of a vibraculum placed on the back of the cell. The cells in some species are provided with a pedunculate operculum, by which it is intended to designate a process, which arising by a short tube from the anterior wall of the cell, immediately beyond the inner margin of the opening, projects forwards and bends over the front of the cell, expanding into a variously-formed limb, and serving as protection to the mouth of the cell in front. The cavity of the tube by which the process arises, becomes, in the expanded portion, continuous with variously disposed grooves or channels, which terminate at the edges of the operculum. This organ affords excellent specific characters (not in this genus alone). Besides the sessile avicularia above noticed, many species of this genus also possess avicularia of another kind, and which are placed on the front of the cell below the opening and towards the inner side, or in other words, towards the middle line of the branch. In this genus, in all those species in which the second avicularium occurs, each individual cell is provided with one. This additional avicularium appears to be composed of a flexible material, and it is very easily broken off, so that in many instances, perhaps throughout an entire specimen the organ itself may be wanting, although its position is clearly evidenced by the existence of a rounded opening in the usual situation of the organ. It is necessary to distinguish this form of flexible (if such it be) avicularium from the truly articulated and movable avicularia, in the form of birds' heads, and which form does not occur in the genus Scrupocellaria.

a. OPERCULATAE. Cells furnished with a pedunculate operculum.

1. S. cervicornis, n. sp.

Veins or channels in the oral operculum, branching so as to resemble the antlers of a stag. The marginal spine next above the pedunculated operculum, bifurcate.

Habitat: Off Cumberland Islands, 25 fathoms, fine grey mud.

A small, delicate, parasitic species, very transparent. The very peculiar markings on the operculum at once distinguish it. The upper margin of the mouth is furnished with five elongated spines, the innermost of which is forked at the extremity.

2. S. diadema, n. sp.

Cells elongate, external side nearly straight, vibraculum sublateral, very prominent. Limit of operculum entire, or obscurely bi-trilobed. A flexible avicularium in front. Ovicell usually with a single row of four or five openings immediately above its mouth.

Habitat: Moreton Bay.

b. INOPERCULATAE. Cells without a pedunculate operculum.

3. S. cyclostoma, n. sp.

Opening of cell nearly or quite circular, margin much thickened, with three or four short indistinct spines above. Vibraculum sublateral. A flexible avicularium in front. Ovicells --- ?

Habitat: Bass Strait, 45 fathoms.

4. S. ferox, n. sp.

Opening of cell broad oval, pointed below; three short indistinct spines above; vibraculum large, sinus deep. An enormous anterior avicularium, as wide as the cell. Ovicell lofty, with numerous punctures over the surface.

Habitat: Louisiade Archipelago. Bass Strait.

Distinguished from the former species by the enormous anterior avicularium, and the form of the opening. Another peculiarity of this species is the curious serrated appearance of the radical tubes.

12. CANDA, Lamouroux.

Character: (B.) cells rhomboidal, sinuated on the outer side for the lodgment of a vibraculum. No sessile avicularium on the upper and outer angle in front. An uncertain number of flexible avicularia, arranged along the middle of the branches, and in much less number than the cells.

This genus is at once distinguished from Scrupocellaria, to which it is otherwise closely allied, by the absence of the sessile avicularium on the upper and outer angle in front, and also by the circumstance, that although there are flexible anterior avicularia, they do not correspond in number with the cells, but seem to be disposed in a special tract along the middle of the branch or internode. The connection of the branches by transverse tubular fibres is not a character of either generic or specific importance, though it is more striking in the only species hitherto known as belonging to this genus, than in any other. These transverse tubular fibres are, like the radical fibres in Scrupocellaria, always inserted, not into the body of a cell, but into a vibraculum. They are evidently of the nature of a byssus.

1. C. arachnoides, Lamouroux.

Cells biserial; opening oval, truncated above, and the upper margin recedent, with a spine on each side, the outer the longer surface of cell covered with transparent granulations.

Habitat: Bass Strait, 45 fathoms.

b. Internodes composed of 2 to 4 cells.

13. EMMA, Gray. Dieffenbach's New Zealand, Volume 2 page 293.

Character. (B.) Cells in pairs or triplets. Opening more or less oblique, subtriangular, partially filled up by a granulated calcareous expansion. A sessile avicularium (not always present) on the outer side, below the level of the opening.

This genus appears to be a natural one, though very closely allied to Tricellaria (Fleming). The more important points of distinction consist in the conformation of the opening of the cell, and in the position of the avicularium when the latter organ is present. The lower half of what would otherwise be the oral opening of the cell is filled up by a thin plate of calcareous matter, granulated on the surface, and by which the actual opening is rendered more or less subtriangular, the mouth being placed just below the apex of the triangle. The margin of the opening is considerably raised, especially at the oval end, so that the opening appears to be situated in a deep depression. This character of opening, however, occurs also in a triserial species of Cellularia from Algoa Bay. The position of the avicularium entirely BELOW the level of the opening on the outer side of the cell, is the peculiar characteristic of Emma as distinguished from Tricellaria, in which that organ when present is placed on the upper and outer angle as in Cellularia proper, and Scrupocellaria. It is worthy of notice that avicularia may be present on every cell in some specimens, and most usually, whilst in others of equal size there will be none at all apparent. So that the position of these organs in this genus, as well as in Tricellaria, is of more importance systematically than even their existence.

1. E. crystallina, Gray, l.c.

Cells in pairs; three spines on the outer edge, the central usually the longest and strongest.

Habitat: Bass Strait, 45 fathoms.

Parasitic upon Polyzoa, etc. circinate branched--branches irregular divaricate. The opening of the cell triangular, very obliquely placed.

2. Emma tricellata, n. sp.

Cells in triplets; three or four long spines on the upper and outer part; a small spine on the inner and lower part of the edge of the opening.

Habitat: Bass Strait.

Parasitic upon Catenicella, etc. Habit long straggling, very like the preceding species. The cells are more infundibuliform, and the avicularium, which, as in E. crystallina is not always present, is larger, but occupies the same position on the cell.

2. Polyzoary continuous throughout.

Fam. 3. BICELLARIADAE. Frond wholly divided into narrow ligulate, dichotomous, bi or multiserial branches; no vibracula. Avicularia when present pedunculate.

14. BICELLARIA, Blainville.

Character. (B.) Cells turbinate, distant. Opening directed more or less upwards. Mouth submarginal. Several curved spines, marginal or submarginal.

1. B. tuba, n. sp.

Opening round, looking nearly directly upwards; a digitiform hollow process below the outer border supporting 2 to 4 long incurved spines; 2 to 3 other long curved submarginal spines behind or above the opening, none below it in front--a solitary spine on the back a short way down the cell. Avicularia very long, trumpet-shaped, arising on the back of the cell.

Habitat: Bass Strait, 45 fathoms.

This species is at once recognisable by the remarkable form and unusual position of the avicularium, and also by the peculiar digitiform spiniferous process on the outer side of the opening.

2. B. gracilis, n. sp.

Cells elongated, slender, opening round or suboval, looking obliquely forwards and upwards; three marginal (sometimes slightly submarginal) spines above and behind the opening, and two much longer curved hair-like spines arising from the anterior and lower edge of the opening. Ovicells globose, subpedunculate, attached to the upper and inner part of the margin of the opening. Avicularia small, like birds' heads.

Habitat: Bass Strait.

A delicate slender species, not unlike B. ciliata or avicularis in habit. The two long spines arising from the anterior edge of the opening suffice to distinguish it from the former of these two species.

3. B. grandis, n. sp.

Cells much elongated outwards, horizontal or projecting portion oblong, rounded at the extremity; 2 to 5 long curved submarginal spines, externally a single dorsal spine about halfway down the cell; opening oval, narrower outwards; very oblique mouth at the outer end. Avicularia ---- ?

Habitat: Bass Strait, 45 fathoms.

Quite distinct from B. ciliata not only in its size, which is nearly three times as great, but in the form of the cell and the opening. The number of spines varies very much, and two or three of them, not unfrequently, arise from a common projecting process or base.

4. B. johnstoniae.

Cells obliquely truncated above with a short spine on the outer angle; opening large, suboval, with an obtuse angle outwardly; margin slightly thickened, wholly unarmed.

Habitat: Off Cumberland Islands, 27 fathoms, fine grey mud.

Of a light grey colour: grows in large loose tufts, composed of long forked ascending branches. It is a very peculiar species, and some difficulty has been found in finding it a place. In the opening of the mouth, and the external short spine, it is a Cellaria; and in the colour and want of distinct articulation, it approaches Acamarchis; whilst in the form of the cell, and their mode of mutual connection, it is a Bicellaria: it differs from all other species of that genus, however, in the absence of any long spines, and in general habit. Were it not referred to that genus, it would probably constitute the type of a distinct one. A curious little trident-like organ is visible in the narrow part of some cells.

15. ACAMARCHIS, Lamouroux.

Character. (B.) Cells elliptical,* closely contiguous; opening very large, margin simple, not thickened. Avicularia not always present, like birds' heads.

(*Footnote. Viewed posteriorly.)

To which may be added, that the species are frequently coloured, red or bluish.

1. A. neritina, Lamouroux.

Habitat: Rio de Janeiro. Broken Bay, New South Wales.

This species appears to be one of the most generally distributed of the Polyzoa; it occurs in nearly every latitude in both hemispheres.

2. A. tridentata. Krauss. Corall. d. Sudsee page 3 figure 2.

Habitat: Bass Strait (?)

This species is placed doubtfully in the Rattlesnake Collection. It occurs, however, in Van Diemen's Land and New Zealand (Dr. Hooker) and is abundant in South Africa.

Fam. 4. CABEREADAE.

Polyzoarium entirely divided into ligulate dichotomous bi or multiserial branches; back nearly covered by large vibracula; avicularia sessile.

16. CABEREA, Lamouroux.

Selbia, Gray. op.c. Volume 2 page 292.

Cells bi-multiserial, in the latter case quincuncial. Posterior surface of branches concealed by large vibracula, which are placed obliquely in a double row, diverging in an upward direction from the middle line, where the vibracula of either row decussate with those of the other. Avicularia when present of the flexible kind, sessile on the front of the cell.

The remarkable feature of this genus resides in the vibracula, which here appear to attain their utmost development. Each vibraculum appears to belong not to a single cell as in Scrupocellaria, but to be common to, or applied to the backs of several. They are more or less pyriform or long oval in shape, and the two rows decussate with each other along the middle of the branch--giving in the narrower species, especially, much the aspect of an ear of barley, and in the wider of a straw plait. The walls of the vibracula are usually thin, and very transparent, so as to allow the outlines of the cells to be seen imperfectly through them. The upper and outer extremity of the vibraculum is bifid, and to the inner horn is articulated the seta, and from the notch between the two horns there is continued nearly, if not quite, to the inner extremity of the organ, and along its upper border, a shallow groove, in which is lodged the seta when in a state of rest. In most species the seta is serrated with distant teeth on one side.

Where there are more than two rows of cells, the marginal cells differ in conformation from the central.

As in Scrupocellaria, the opening of the cell is sometimes protected by a pedunculate operculum. The genus, therefore, may, like that, admit of being divided into sections, distinguished respectively by the presence or absence of a pedunculate operculum.

a. Operculatae.

1. C. rudis, n. sp.