Chapter VIII: Part 8

a, Shell (here enclosed by a growth of the mantle).

b, The nuchal plate (here a cartilage).

c, (The reference line should be continued through the black area
representing the shell to the outline below it), the integument
covering the visceral hump.

d, The reflected portion of the mantle-skirt forming the sac which
encloses the shell.

e, The inferior margin of the mantle-skirt (mouth of the pallial
chamber).

f, The pallial chamber.

g, The vertically cut median portion of the siphon.

i, The valve of the siphon.

m, The two upper lobes of the fore-foot.

n, The long prehensile arms of the same.

o, The fifth or lowermost lobe of the fore-foot.

p, The third lobe of the fore-foot.

q, The buccal membrane.

v, The upper beak or jaw. s, The lower beak or jaw.

t, The lingual ribbon.

x, The viscero-pericardial sac.

n.c, The nerve-collar.

cr, The crop.

gizz, The gizzard.

an, The anus.

c.t, The left ctenidium or gill-plume.

vent, Ventricle of the heart.

a.b.v, Afferent branchial vessel.

e.b.v, Efferent branchial vessel.

re, Renal glandular mass.

n.n.a, Left nephridial aperture.

visc.per.apert, Viscero-pericardial aperture (see fig. 29).

br.b, Branchial heart.

app, Appendage of the same.

i.s, Ink-bag.]

_Luminous Organs._--In certain Oigopsida living in deep water, e.g.
_Histioteuthis, Calliteuthis, Histiopsis, Pterygioteuthis_, the
surface of the skin bears photogenous organs directed towards the oral
extremity. Anatomically these consist of a deeper photogenous layer
and a more superficial refracting layer. In some cases, e.g.
_Pterygioteuthis_, they occur even within the mantle-cavity.

_Fins._--In the majority of the Decapoda and in the _Cirrhoteuthidae_,
the mantle is produced into lateral symmetrical expansions which have
the function of fins. They originate at the aboral extremity where
they remain in _Spirula_ (fig. 18). In most other Oigopsida they are
terminal, but more dorsal than ventral, e.g. _Loligopsis_ (fig. 16),
and there may be two on each side, as in _Grimalditeuthis_. In other
cases they extend laterally along a greater length of the body, as in
_Sepia_ (fig. 15). In _Ctenopteryx_ they have a superficial
resemblance to the fins of fishes, consisting of a thin membrane
supported by a series of muscular rods.

_Chromatophores._--These are characteristic of the Dibranchiata,
apparently absent in _Nautilus_. They are originally single cells of
ectodermic origin which sink below the epidermis and become connected
with radiating muscular fibres. The cells are single but multinuclear.
Different cells contain pigments of different colours, yellow, brown,
red or blue. Each cell in life is in constant tremulous movement;
under the influence of nervous excitement the cells are suddenly
expanded or contracted, producing blushes of colour and pallor. By
reflex action of which the afferent stimulus acts upon the eyes as in
fishes, the chromatophores assume a condition which approximates the
colour of the animal to that of surrounding objects. In the Decapoda
there are also reflecting elements which produce iridescent hues.

_Aquiferous Cavities._--In addition to the pockets into which the
tentacular arms of Decapoda are retracted, there are in several
Dibranchiata cavities in the integument which open to the exterior by
special pores but have no communication with the vascular system or
other internal cavities of the body. In _Ocythoe_ there are such pores
on the back of the head and at the base of the funnel; buccal pouches
on the ventral side of the mouth, internal to the arms, occur in some
genera, one in _Loligo_, two in _Sepia_. In some species of _Sepia_
there are pouches in the mantle.

_Alimentary Tube._--The principal differences from _Nautilus_ are the
following:--the mandibles are similar in shape, but are chitinous, not
calcified. In the radula there are three teeth on each side of the
median tooth in each row, except in _Gonatus_, in which there are only
two lateral teeth, and the _Cirrhoteuthidae_, in which the radula has
entirely disappeared. In front of the radula is the so-called tongue,
a fleshy projection corresponding to the sub-radular organ of other
Mollusca.

oe, Oesophagus.

v, The stomach opened longitudinally.

x, Probe passed through the pylorus.

c, Commencement of the caecum.

e, Its spiral portion.

i, Intestine.

a, Ink-bag.

b, Its opening into the rectum.]

In most of the Dibranchiata there are two pairs of salivary glands. In
the Decapoda the ducts of the posterior pair unite into a median duct
which opens on the surface of the sub-radular organ. The anterior pair
is but slightly developed except in the Oigopsida. In the Octopoda
there are also two pairs, but the posterior pair, except in
_Cirrhoteuthis_ where they are absent, are large and displaced
backwards, being situated near the oesophageal proventriculus.
Connected with the intestine immediately beyond the pylorus is a
thin-walled caecum, spherical in _Rossia_ and _Leachia_, elongated in
_Loligo_, but usually coiled into a spiral (fig. 27). The hepatic
ducts open into the caecum. The liver is developed as a paired gland,
more or less fused into one in the adult, but the ducts are always
paired. The ducts are covered by a number of glandular follicles
forming what is called the pancreas.

The ink-sac, absent in _Nautilus_, is a rectal caecum developed from
its dorsal wall. It is present in all Dibranchiata except _Octopus
arcticus, O. piscatorum_ and _Cirrhoteuthis_. It consists of a deeper
part or gland proper and a reservoir. It extends to the posterior
extremity of the body in _Sepia_, but in _Octopoda_ is usually
embedded in the surface of the liver. The pigment of the secretion is
melanin, and its function is to produce a dense opacity in the water,
which conceals the animal.

_Vascular System_ (fig. 28).--The ventricle lies in the pericardial
cavity, except in Octopoda where this cavity is much reduced. The
auricles, one pair, are contractile expansions of the efferent
branchial vessels. The heart gives off an anterior or cephalic and a
posterior or abdominal aorta. The vascular system is almost perfect,
arteries and veins being united by capillaries. The principal vein is
a vena cava passing backwards ventrally from the cephalic region and
dividing into two afferent branchial veins, each of which receives a
pallial and an abdominal vein. Each of these afferent branchial
vessels is enclosed in the cavity of a renal organ and is covered
externally by the glandular tissue which forms the excretory part of
the "kidney" (fig. 29). Each afferent vessel is expanded into a
contractile branchial heart, which is provided with a glandular
appendage. The latter corresponds to the glandular masses which are
attached to the afferent branchial veins in _Nautilus_, and to the
pericardial glands of other Molluscs.

br, Branchiae (ctenidia).

c, Ventricle of the heart.

a, Anterior artery (aorta).

a', Posterior artery.

v, The right and left auricles (enlargements of the efferent
branchial veins).

v', Efferent branchial vein on the free face of the gill-plume.

v.c, Vena cava.

vi, vc', Afferent branchial vessels (branches of the vena cava, see
fig. 29).

vc", Abdominal veins.

x, Branchial hearts and appendages.

re, e, Glandular substance of the nephridia developed on the wall of
the great veins on their way to the gills. The arrows indicate the
direction of the blood-current.]

v.c, Vena cava.

r.d.v.c, Right descending branch of the same.

r.s.v.c, Left descending branch of the same.

v.b.a, Vein from the ink-bag.

v.m, Mesenteric vein.

v.g, Genital vein.

v.a.d, Right abdominal vein.

v.a.s, Left abdominal vein.

v.p.d, Right pallial vein.

v.p.s, Left pallial vein.

c.b, Branchial heart.

x, Appendage of the same.

c.v, Capsule of the branchial heart.

np, External aperture of the right nephridial sac.

y, Reno-pericardial orifice placing the left renal sac or nephridium
in communication with the viscero-pericardial sac, the course of
which below the nephridial sac is indicated by dotted lines.

y', The similar orifice of the right side.

a.r, Glandular renal outgrowths.

w.k, Viscero-pericardial sac (dotted outline).]

_Coelom._--The coelom forms a large sac with a constriction between
the anterior or pericardial division and the posterior or genital
division, and it is produced into lateral diverticula which contain
the branchial hearts; but in the Octopoda the pericardial division is
suppressed and the genital division communicates by long ducts with
sacs containing the appendages of the branchial hearts. The renal sacs
communicate with the pericardium by pores near the external renal
apertures; in the Octopoda the reno-pericardial openings are in the
capsules of the branchial hearts. The genital ducts pass from the
genital coelom to the exterior. They are paired in female Oigopsida
and Octopoda except _Cirrhoteuthidae_, but only the left persists in
the males of all Dibranchiata, and in the female Myopsida.

buc, The buccal mass.

ped, Pedal ganglion.

opt, Optic ganglion.

cer, Cerebral ganglion.

pl, Pleural ganglion.

visc, Visceral ganglion.

oes, Oesophagus.

f, Foramen in the nerve-mass formed by pedal, pleural and visceral
ganglion-pairs, traversed by a blood-vessel.]

In the oviduct is a glandular enlargement, and in addition to this the
females are provided with the so-called nidamental glands which are
developed on the somatic wall of the pallial cavity, one on each side
of the rectum, except in certain Oigopsida (_Enoploteuthis, Cranchia,
Leachia_) and in the Octopoda, in which these organs are absent. The
latter fact is related to the habit of the majority of the Octopoda of
guarding or "incubating" their eggs, which have little protective
covering. In the other cases the eggs are surrounded by a tough
gelatinous elastic material secreted by the nidamental glands.

bg, Buccal ganglion.

cer, Cerebral ganglion.

ped, Pedal ganglion.

pl, Pleural, and visc., visceral region of the pleuro-visceral
ganglion.

gang. stell, The right stellate ganglion of the mantle connected by
a nerve to the pleural portion.

n.visc, The right visceral nerve.

n.olf, Its (probably) olfactory branches.

n.br, Its branchial branches.]

The vas deferens is at first narrow and convoluted, then dilates into
a vesicula seminalis at the end of which is a glandular diverticulum
called the prostate. By the vesicula and the prostate the
spermatophores are formed. These have a structure similar to those of
_Nautilus_, and in the Octopoda may be as much as 50 mm. in length.
Beyond the prostate the duct opens into a large terminal reservoir
which has been called Needham's sac, and in which the spermatophores
are stored.

_Nervous System and Sense-Organs._--The figures (30, 31, 32)
representing the nerve-centres of _Octopus_ serve to exhibit the
disposition of these parts in the Dibranchiata. The ganglia are more
distinctly swollen than in _Nautilus_. In _Octopus_ an infra-buccal
ganglion-pair are present, corresponding to the buccal ganglion-pair
of Gastropoda. In Decapoda a supra-buccal ganglion-pair connected with
these are also developed. Instead of the numerous radiating pallial
nerves of _Nautilus_, we have in the Dibranchiata on each side (right
and left) a large pleural nerve passing from the pleural portion of
the pleuro-visceral ganglion to the mantle, where it enlarges to form
the stellate ganglion. From each stellate ganglion nerves radiate to
supply the powerful muscles of the mantle-skirt. The two stellate
ganglia are connected, except in _Sepiola_, by a transverse
supra-oesophageal commissure, which represents the pallial cords
united by a commissure above the intestine in Amphineura. The nerves
from the visceral portion of the pleuro-visceral ganglion have the
same course as in _Nautilus_, but no osphradial papilla is present. An
enteric nervous system is richly developed in the Dibranchiata,
connected with the somatic nervous centres through the buccal ganglia,
as in the Arthropoda through the stomato-gastric ganglia, and
anastomozing with deep branches of the visceral nerves of the
viscero-pleural ganglion-pair. It has been especially described by A.
Hancock in _Ommatostrephes_. Upon the stomach it forms a single large
and readily detected gastric ganglion.

KK, Cephalic cartilages (see fig. 8).

C, Cornea (closed).

L, Lens.

ci, Ciliary body.

Ri, Internal layer of the retina.

Re, External layer of the retina.

p, Pigment between these.

o, Optic nerve.

go, Optic ganglion.

k and k', Capsular cartilage.

ik, Cartilage of the iris.

w, White body.

ae, Argentine integument.]

In the Dibranchiate division of the Cephalopoda the greatest
elaboration of the dioptric apparatus of the eye is attained, so that
we have in this class the extremes of the two lines of development of
the Molluscan eye, those two lines being the punctigerous and the
lentigerous. The structure of the Dibranchiate's eye is shown in
section in fig. 14, C, and in fig. 33, and its development in figs. 34
and 37. The open sac which forms the retina of the young Dibranchiate
closes up, and constitutes the posterior chamber of the eye, or
primitive optic vesicle (fig. 37, A, poc). The lens forms as a
structureless growth, secreted by both the internal and external
surfaces of the front wall of the optic vesicle (fig. 37, B, l). The
integument around the primitive optic vesicle which has sunk below the
surface now rises up and forms firstly nearest the axis of the eye the
iridian folds (if in B, fig. 37; ik in fig. 33; Ir in fig. 14), and
then secondly an outer circular fold grows up like a wall and
completely closes over the iridian folds and the axis of the primitive
vesicle (fig. 33, C). This covering is transparent, and is the cornea.
In the oceanic Decapoda the cornea does not completely close, but
leaves a central aperture traversed by the optic axis. These forms are
termed Oigopsidae by C. d'Orbigny, whilst the Decapoda with closed
cornea are termed Myopsidae. In the Octopoda the cornea is closed, and
there is yet another fold thrown over the eye. The skin surrounding
the cornea presents a free circular margin, and can be drawn over the
surface of the cornea by a sphincter muscle. It thus acts as an
adjustable diaphragm, exactly similar in movement to the iris of
Vertebrates. _Sepia_ and allied Decapods have a horizontal lower
eyelid, that is to say, only one-half of the sphincter-like fold of
integument is movable. The statocysts are situated ventrally between
the pedal and visceral ganglia, and are entirely enclosed in the
cranial cartilage. The cavity of each is continued into a small blind
process which is the remnant of the embryonic connexion of the vesicle
with the external surface. The sensory epithelium is at the anterior
end of the vesicle forming a macula acustica, and in the cavity is a
single otolith, partly calcareous and partly organic except in
_Eledone_, in which it is entirely organic. The nerve arises from the
cerebral ganglion on each side and passes through the pedal ganglion.

There is no branchial osphradium in the Dibranchiata corresponding to
that of _Nautilus_, but the olfactory organ or rhinophore near the eye
is present. In _Sepia_ and the majority of the Dibranchiata it is a
simple pit, in some of the Oigopsida it is a projection which may be
stalked.

A, First appearance of the eye as a ring-like upgrowth.

B, Ingrowth of the ring-like wall so as to form a sac, the primitive
optic vesicle of _Loligo_.]

_Reproduction and Development._--The modification of one or a pair of
the arms in the male for purposes of copulation has already been
described. In many genera the sexes differ from one another in other
characters also. As a rule the males are more slender or smaller than
the females. The maximum degree of sexual dimorphism occurs in
_Argonauta_ among the Octopods; in this genus the female may be
fifteen times as large as the male, and the peculiar modification of
the dorsal arms for the secretion of the shell occurs in the female
only, no shell being formed in the male. In most cases the females are
much more numerous than the males, but the opposite relation appears
to exist in those Octopoda in which the hectocotylus is autotomous,
for as many as four hectocotyli have been found in the pallial cavity
of a single female. When the hectocotylus is not detached it is
usually inserted into the pallial cavity of the female so as to
deposit the spermatophores in or near the aperture of the oviduct, but
in _Sepia_ and _Loligo_ they are merely deposited on the ventral lobes
of the buccal membrane.

The eggs are laid shortly after copulation. In the Octopoda and in
_Sepia_, _Sepiola_ and _Rossia_, each egg has a separate envelope
continued into a long stalk by which it is attached with several
others in a cluster. In _Argonauta_ the eggs are carried by the female
in the cavity of the shell. In _Loligo_ the eggs are very numerous,
and are enclosed in cylindrical transparent gelatinous strings united
at one end into a cluster.

The Cephalopoda appear to be the only Invertebrates in which the egg
is mesoblastic and telolecithal like that of Vertebrata. This is the
result of the large quantity of the yolk, and the position the latter
assumes in relation to the blastoderm. In all other Mollusca the
segmentation is complete though in some cases very unequal. In the egg
of _Loligo_, which has been chiefly studied (fig. 35), the
protoplasmic pole is at the narrower end of the egg, and segmentation
is restricted to this end, forming a layer of ectoderm cells. From one
part of the periphery of the ectoderm proliferation of cells takes
place and gives rise to a layer of scattered nuclei over the whole
surface of the yolk. The region of proliferation marks the anal side
of the ectoderm, and the layer of nuclei forms the perivitelline
membrane. This process must be regarded as equivalent to the first
stage of invagination, the yolk being surrounded by hypoblast cells or
their nuclei. Later on the same anal edge of the ectoderm forms
another cellular layer, the endoderm proper, which forms a continuous
sheet below the ectoderm.

The mesoderm also originates at the anal side of the ectoderm and
extends in two bands right and left between ectoderm and endoderm.
After the mesoderm is thus established, a little vesicle lying upon
and open to the yolk is formed from the endoderm, and this vesicle
ultimately gives rise to the stomach, the two lobes of the liver and
the intestine. The buccal mass and oesophagus arise from a stomodaeal
invagination, and the anus is formed later from a short proctodaeal
invagination.

The external changes of form are as follows:--The mantle is the middle
of the embryonic area, and in its centre is the shell-gland, which,
however, behaves in a different way from that seen in other Molluscs.
Its borders grow inwards and approach each other to form the
shell-sac. E. Ray Lankester showed that in _Argonauta_ and other
Octopods the shell-sac disappears before it is closed up, but in other
forms except _Spirula_ it closes completely and the shell develops
within it. The lateral and posterior borders of the embryo form the
foot, and these borders grow out into ten or eight lobes which become
the arms, and which at first, as seen in fig. 35 (8), are entirely
posterior to the mouth. Development actually shows the anterior arms
gradually growing round the mouth and uniting in front of it. Between
the mantle and the foot are two ridges which form the funnel, and
their position shows them to be the epipodia. The otocysts and eyes
are formed as invaginations of ectoderm, the former behind the eyes,
at the sides of the funnel. All the nerve-centres, cerebral, visceral,
pedal and optic, are formed as proliferations of the ectoderm. At the
sides of the optic ganglia a pair of ectodermic invaginations are
formed, which in the adult become the white bodies of the eyes,
surrounding the optic ganglion. These are vestiges of lateral cerebral
lobes which degenerate in the course of development.

1. View of the cleavage of the egg during the first formation of
embryonic cells.

2. Lateral view of the egg at a little later stage. a, Limit to
which the layer of cleavage-cells has spread over the egg; b,
portion of the egg (shaded) as yet uncovered by cleavage-cells; ap,
the auto-plasts; kp, cleavage-pole where first cells were formed.

3. Later stage, the limit (a) now extended so as to leave but little
of the egg-surface (b) unenclosed. The eyes (d), mouth (e) and
mantle-sac (u) have appeared.

4. Later stage, anterior surface, the embryo is becoming nipped off
from the yolk-sac (g).

5. View of an embryo similar to (3) from the cleavage-pole or
centro-dorsal area.

6. Later stage, posterior surface.

7. Section in a median dorso-ventral and antero-posterior plane of
an embryo of the same age as (4).

8. View of the anterior face of an older embryo.

9. View of the posterior face of an embryo of the same age as (8).

Letters in (3) to (9):--a, lateral fins of the mantle; b,
mantle-skirt; c, supra-ocular invagination to form the "white body";
d, the eye; e, the mouth; f^1, f^2, f^3, f^4, f^5, the five paired
processes of the fore-foot; g, rhythmically contractile area of the
yolk-sac, which is itself a hernia-like protrusion of the median
portion of the fore-foot; h, dotted line showing internal area
occupied by yolk (food-material of the egg); k, first rudiment of
the epipodia (paired ridges which unite to form the siphon or
funnel); l, sac of the radula or lingual ribbon; m, stomach; n,
rudiments of the gills (paired ctenidia); o, the otocysts--a pair of
invaginations of the surface of the epipodia; p, the optic ganglion;
q, the distal portion of the ridges which form the siphon, k being
the basal portion of the same structure; r, the vesicle-like
rudiment of the intestine formed independently of the parts
connected with the mouth, s, k, m, and without invagination; s,
rudiment of the salivary glands; t in (7), the shell-sac at an
earlier stage open (see fig. 36), now closed up; u, the open
shell-sac formed by an uprising ring-like growth of the
centro-dorsal area; w in (5), the mantle-skirt commencing to be
raised up around the area of the shell-sac. In (7) mes points to the
middle cell-layer of the embryo, ep to the outer layer, and h to the
deep layer of fusiform cells which separates everywhere the embryo
from the yolk or food-material lying within it.]

The coelomic cavity appears as a symmetrical pair of spaces in the
mesoderm, right and left of the intestine, and from it grow out the
genital ducts and the renal organs. The gonad develops from the wall
of the coelom.

_Phylogeny and Classification._--The order is divided into two
sub-orders, Decapoda and Octopoda, by the presence or absence of the
tentacular arms. The Decapoda are more adapted for swimming than the
Octopoda, the body being usually provided with fins. In the former
also there is generally an internal shell of considerable size, often
calcined, while in the Octopoda only the merest vestiges of a shell
remain. There can be no doubt that the Octopoda were derived from the
Decapoda, although from the absence of skeletal structures fossil
remains of Octopods are almost entirely unknown. _Palaeoctopus_,
however, occurs in the Cretaceous, while shells of _Argonauta_ do not
appear before the Pliocene. The Decapoda are abundantly represented in
the Secondary formations by the _Belemnitidae_, whose shell (fig. 19)
consists of a straight conical phragmacone covered posteriorly by a
very thick rostrum, and produced anteriorly into a thin long
proöstracum which is only occasionally preserved. In certain cases
remains of the arms provided with hooks, and of the ink-sac, have been
recognized. The _Belemnitidae_ appear first in the Upper Trias, attain
their maximum development in the Jurassic rocks, and are not continued
into the Tertiary period, though represented in the Eocene by a few
allied forms.

There is no difficulty in deriving the typical existing Decapoda from
_Belemnitidae_, and many of the extinct forms may have been directly
ancestral. Chitinous "pens" like that of _Loligo_, however, begin to
appear in the Jurassic and Cretaceous rocks, so that in this case as
in many others the parent form and the modified form existed
contemporaneously, and the latter alone has survived. The oldest
shells of the _Sepia_ type are from the Eocene, and it is perhaps
possible that the _Sepiidae_ arose separately from the Belemnites.

It is a curious fact that no fossil specimens of the genus _Spirula_
have been found, but this may be due to the fact that it occurs only
in deep water. At any rate there is no evidence that the shell of
_Spirula_ has lost a rostrum and a proöstracum; its characters must be
regarded as primitive, not secondary. In the characters of the
protoconch and of the commencement of the siphuncle, the shell of
_Spirula_ agrees with that of the Ammonoids, and in both its position
is ventral, although in most Ammonoids the shell being exogastric the
ventral side is the convex or external, while in _Spirula_ the shell
is endogastric and the siphuncle internal. The fact that the shell is
not completely enclosed by the mantle is also a primitive character.

With regard to the general morphology of the Cephalopoda, it is
difficult to reconcile the existence of two pairs of renal tubes as
well as a pair of genital ducts in _Nautilus_ with the view that the
original Mollusc was unsegmented and had only one pair of
coelomoducts. Considering the great specialization, however, and high
degree of organization of the Cephalopods, it is evident that the
earliest Nautiloid whose remains are known to us must have had a long
evolutionary history behind it, and such metamerism as exists may have
been developed in the course of its own history. In the other
direction the evidence seems to prove that the Dibranchiata with only
two renal ducts have been derived from the Tetrabranchiata.

SUBORDER 1. DECAPODA.--Four pairs of ordinary non-retractile arms
which are shorter than the body, and one pair of tentacular arms,
situated between the third and fourth normal arms on each side and
retractile within special pouches. Suckers pedunculated and provided
with horny rings, on the tentacular arms confined usually to the
distal extremities. Usually a well-developed internal shell, and
lateral fins on the edges of the body. Heart in a coelomic cavity;
nidamentary glands usually present.

A, Same stage as fig. 35 (4).

B, Same stage as fig. 35 (8); only the left side of the sections is
drawn, and the food-material which occupies the space internal to
the membrane ym is omitted.

al, Rectum.

is, Ink-sac.

ep, Outer cell-layer.

mes, Middle cell-layer.

ym, Deep cell-layer of fusiform cells (yolk-membrane).

ng, Optic nerve-ganglion.

ot, Otocyst.

wb, The "white body" of the adult ocular capsule forming as an
invagination of the outer cell-layer.

mtf, Mantle-skirt.

g, Gill.

ps, Pen-sac or shell-sac, now closed.

dg, Dorsal groove.

poc. Primitive optic vesicle, now closed (see fig. 34).

l, Lens.

r, Retina.

soc, Second or anterior optic chamber still open.

if, Iridean folds.

C, The primitive invagination to form one of the otocysts, as seen
in fig. 35 (5) and (6).]

Tribe 1. _Oigopsida_.--A wide aperture in the cornea. Two oviducts in
the female. In fossil genera and _Spirula_, shell has a multilocular
phragmacone with a siphuncle; initial chamber globular and larger than
the second chamber. The most ancient forms characterized by the small
size of the rostrum and proöstracum, and large size of the
phragmacone. In the living genera, except _Spirula_, the shell is a
chitinous gladius.

Fam. 1. _Belemnoteuthidae_. Extinct; shell with well-developed
phragmacone, and rostrum merely a calcareous envelope; siphuncular
necks directed backwards as in Nautiloidea; ten equal arms provided
with hooks. _Phragmoteuthis_, Trias. _Belemnoteuthis_, Jurassic and
Cretaceous. _Acanthoteuthis_, Jurassic.

Fam. 2. _Aulacoceratidae_. Extinct; phragmacone with widely
separated septa; rostrum well developed and claviform.
_Aulacoceras_, Trias. _Atractites_, Trias and Jurassic.
_Xiphoteuthis_, Lias.

Fam. 3. _Belemnitidae_. Extinct; phragmacone short with ventral
siphuncle, prolonged dorsally into long proöstracum; rostrum large
and cylindrical. _Belemnites_, 350 species from Jurassic and
Cretaceous. _Diploconus_, Upper Jurassic.

Fam. 4. _Belopteridae_. Extinct; rostrum and phragmacone well
developed, phragmacone often curved; initial chamber small.
_Beloptera_, Eocene. _Bayanoteuthis_, Eocene. _Spirulirostra_,
Miocene.

Fam. 5. _Spirulidae_. Dorsal and ventral sides of posterior
extremity of shell uncovered by mantle; no rostrum or proöstracum;
shell calcareous, coiled endogastrically and sipnunculated; fins
posterior. _Spirula_, three living species known, abyssal.

Fam. 6. _Ommatostrephidae_. Shell internal and chitinous, ending
aborally in a little narrow cone; tentacular arms short and thick;
suckers with denticulate rings. _Ommatostrephes_, fins aboral,
simple and rhomboidal, British. _Ctenopteryx_, fins pectinate, as
long as the body; _Bathyteuthis_, fins terminal, rudimentary;
tentacular arms, filiform; abyssal. _Rhynchoteuthis_, tentacular
arms united to form a beak-shaped appendage. _Symplectoteuthis.
Tracheloteuthis. Doridicus. Architeuthis_; this is the largest of
Cephalopoda, reaching 60 ft. in length including arms.

Fam. 7. _Thysanoteuthidae_. Arms enlarged, bearing two rows of
suckers and filaments; fins triangular, extending whole length of
body. _Thysanoteuthis_, Mediterranean.

Fam. 8. _Onychoteuthidae_. Fins terminal; tentacular arms long;
suckers with hooks. _Onychoteuthis_, hook-bearing suckers on
tentacular arms only. _Enoploteuthis_, hook-bearing suckers on all
the arms. _Veranya_, body very short, tentacular arms atrophied in
the adult, Mediterranean. _Chaunoteuthis_, body elongated,
tentacular arms atrophied. _Pterygioteuthis. Ancistroteuthis.
Abralia. Teleoteuthis. Lepidoteuthis._

Fam. 9. _Gonatidae_. Body elongated; fins terminal; radula with only
two lateral teeth. _Gonatus_.

Fam. 10. _Cheiroteuthidae_. Tentacular arms long, not retractile;
resisting apparatus well developed. _Cheiroteuthis_, suckers along
the whole length of the tentacular arms. _Doratopsis_, body very
long and slender with aboral spine, dorsal arms very short.
_Histioteuthis_, six dorsal arms united by membrane, photogenous
organs present. _Histiopsis_, membrane of dorsal arms only half-way
up the arms, photogenous organs present. _Calliteuthis_, no brachial
membrane, photogenous organs present. _Grimalditeuthis_, two fins on
each bide, no tentacular arms.

Fam. 11. _Cranchiidae_. Eight normal arms, very short; eyes
prominent; fins small and terminal. _Cranchia_, body short,
purse-shaped, normal arms short, fins entirely aboral. _Loligopsis_,
body elongated, conical, tentacular arms slender. _Leachia_,
tentacular arms absent, funnel without a valve. _Taonius_, body
elongated, normal arms, rather short, eyes pedunculated.

A, _Pinnoctopus cordiformis_, Quoy and Gain (from New Zealand).

B, _Tremoctopus violaceus_, Ver. (from the Mediterranean).

C, _Cranchia scabra_, Owen (from the Atlantic Ocean; one of the
Decapoda).

D, _Cirrhoteuthis Mulleri_, Esch. (from the Greenland coast).]

Tribe 2. _Myopsida_.--No aperture in the cornea. Left oviduct only
developed in female. Internal shell without a distinct phragmacone,
calcified or simply chitinous.

Fam. 1. _Sepiidae_. Body wide and flat; fins narrow, extending the
whole length of the body; shell calcareous and laminated.
_Belosepia_, a rudiment of rostrum and phragmacone present in shell,
Eocene. _Sepia_, shell with a rostrum, British. _Sepiella_, shell
without a rostrum.

Fam. 2. _Sepiolidae_. Body short, rounded at the aboral end; fins
rounded, inserted in middle of body-length; shell chitinous, small
or absent. _Sepiola_, head united to mantle dorsally, British.
_Rossia_, head not united to mantle, British. _Stoloteuthis_ and
_Inioteuthis_, without shell. _Heteroteuthis. Euprymna._

Fam. 3. _Idiosepiidae_. Body elongated, with rudimentary terminal
fins; internal shell almost lost. _Idiosepius_, 1.5 cm. long, Indian
Ocean.

Fam. 4. _Sepiadariidae_. Body short; mantle united to head dorsally;
no shell. _Sepiadarium_, Pacific Ocean. _Sepioloidea_, Australian.

Fam. 5. _Loliginidae_. Body elongated and conical; fins extending
forward beyond the middle of body-length; shell chitinous, well
developed. _Loligo_, fins triangular, aboral, British.
_Sepioteuthis_, fins rounded, extending along whole of body-length.
_Loliolus. Loliguncula._ The following fossil genera, known only by
their gladius and ink-sac, have been placed near
_Loligo_:--_Teuthopsis, Beloteuthis_ and _Geoteuthis_, Lias;
_Phylloteuthis_, Cretaceous; _Plesioteuthis_, Jurassic and
Cretaceous.

SUBORDER 2. OCTOPODA.--Only four pairs of arms, all similar and longer
than the body. Body short and rounded aborally. Suckers sessile. Heart
not contained in coelom. No nidamentary glands.

Tribe I. _Leioglossa_.--No radula. Arms united by a complete membrane.
Fins on sides of body.

Fam. _Cirrhoteuthidae_. Tentacular filaments on either side of the
suckers. _Cirrhoteuthis_, pallial sac prominent, fins large,
pelagic. _Opisthoteuthis_, body flattened, with small fins,
deep-sea. _Vampyroteuthis_, four fins. _Palaeoctopus_, fossil,
Cretaceous.

Tribe 2. _Trachyglossa._--Radula present. No fins.

Fam. 1. _Amphitretidae_. Arms united by membrane; funnel attached to
mantle, dividing the pallial aperture into two. _Amphitretus_,
pelagic.

Fam. 2. _Alloposidae_. All arms united by membrane; mantle joined
to head by dorsal band and two lateral commissures. _Alloposus_,
pelagic.

Fam. 3. _Octopodidae_. Arms long and equal, without membrane;
hectocotylus not autotomous. No cephalic aquiferous pores.
_Octopus_, two rows of suckers on each arm, British. _Eledone_,
single row of suckers on each arm. _Scaeurgus. Pinnoctopus.
Cistopus. Japetella._

Fam. 4. _Philonexidae_. Hectocotylus autotomous; arms unequal in
size; aquiferous pores on head and funnel. _Tremoctopus_, two dorsal
pairs of arms united by membrane. _Ocythoë_, without interbrachial
membrane.

Fam. 5. _Argonautidae_. Hectocotylus autotomous; no interbrachial
membrane; extremities of dorsal arms in female expanded and
secreting a shell; males very small, without shell. _Argonauta_.

LITERATURE.--Use has been freely made above of the article by E. Ray
Lankester, on _Mollusca_, in the 9th edition of this Encyclopedia. For
the chief modern works, see Bashford Dean, "Notes on Living Nautilus,"
_Amer. Nat._ xxxv., 1901; Arthur Willey, "Contribution to the Natural
History of the Pearly Nautilus," A. Willey's _Zoological Results_, pt.
vi. (1902); Foord, _Cat. Fossil Cephalopoda in British Museum_;
Alpheus Hyatt, "Fossil Cephalopods of the Museum of Comp. Zoology,"
_Bull. Mus. Comp. Zool._ (Cambridge, U.S., 1868); Jalta, "I Cefalopodi
viventi nel golfo di Napoli," _Fauna und Flora des Golfes von Neapel_,
xxiii. (1896); Joubin, "Céphalopodes de l'atlantique nord," "Céph. de
la Princesse Alice," _Camp. sci. Albert I^er de Monaco_, ix. (1895),
xxii. (1900); Paul Pelseneer, "Mollusca," in the _Treatise on
Zoology_, edited by E. Ray Lankester. (J. T. C.)

CEPHEUS, in Greek mythology, the father of Andromeda (q.v.); in astronomy, a constellation of the northern hemisphere, mentioned by Eudoxus (4th century B.C.) and Aratus (3rd century B.C.). Ptolemy catalogued 13 stars in this constellation, Tycho n, and Hevelius 51. The most interesting star in it is [delta] _Cephei_, a remarkable double star, the brighter component of which is a short period variable (5.37 days), with a range in magnitude of 3.7 to 4.9; it is also a spectroscopic binary.

CEPHISODOTUS, the name of the father and of the son of Praxiteles, both sculptors like himself. The former must have flourished about 400 B.C. A noted work of his was Peace bearing the infant Wealth, of which a copy exists at Munich. Peace is a Madonna-like figure of a somewhat conservative type; the child Wealth is less successful. Cephisodotus also made, like his son, a figure of Hermes carrying the child Dionysus, unless indeed ancient critics have made two works of one. He made certain statues for the city of Megalopolis, founded in 370 B.C. Of the work of the younger Cephisodotus, his grandson, we have no remains; he was a prolific sculptor of the latter part of the 4th century B.C., especially noted for portraits, of Menander, of the orator Lycurgus, and others (see J. Overbeck, _Antike Schriftquellen_, p. 255).

CERAM (_Sirang_), an island of the Dutch East Indies, in the Molucca group, lying about 3° S., and between 127° 45' and 131° E. Its length is a little over 200 m., its greatest breadth about 50 m., and its area, including neighbouring islets, 6621 sq. m. It consists of two parts, Great Ceram and Little Ceram or Huvamohel, united by the isthmus of Taruno; and, for administrative purposes, is assigned to the residency of Amboyna, being divided into Kairatu or West Ceram, Wahai and Amahai, the northern and the southern parts of Middle Ceram, and Waru or Eastern Ceram. No central chain of mountains stretches west and east through the island, but near the north coast hills, rising 2300 to 2600 ft., slope steeply to the shore. Near the south coast, west of the Bay of Elpaputeh, a complex mass of mountains forms a colossal pyramid, with peaks rising to nearly 5000 ft. The isthmus connecting the two parts of the island is very narrow, and has a height of only 460 to 490 ft. The chief rivers flow north and south into bays, but are navigable only for a few miles during the rainy season. The rainfall is very heavy, amounting to 121 in. (mean annual) on the south coast. On the north coast the bays of Savai and Waru are accessible for small vessels. The geological structure, consisting chiefly of eruptive rocks and crystalline limestone, is similar to that of northern Amboyna. In the eastern section the prevailing rock is crystalline chalk, similar to that of Buru. Several hot springs occur, and earthquakes are not infrequent. About 4000 persons perished in the earthquake of 1899. A large part of the interior is covered with dense forests, and except along the coast the population is scanty. For the naturalist Ceram is without much interest, lacking characteristic species or abundance of specimens. The Bandanese pay occasional visits to shoot bears and deer; there are numbers of wild goats and cattle; and among birds are mentioned cassowaries, cockatoos, birds of paradise, and the swallows that furnish edible nests. A large number of fish are to be found in the various rivers; and as early as 1860 no fewer than 213 species were described. The most valuable timber tree is the iron-wood. Rice, maize, cocoa-nuts, sugar-cane and a variety of fruits are grown; and some tobacco is exported to Europe; but by far the most important production is the sago palm, which grows abundantly in the swampy districts, especially of Eastern Ceram, and furnishes a vast supply of food, not only to Ceram itself, but to other islands to the east. The Dutch have established cocoa and coffee plantations at various points. The coast-villages are inhabited by a mixed Malay population, Buginese, Macassars, Balinese and other races of the archipelago. The interior is occupied by the aborigines, a people of Papuan stock. They are savages and head-hunters. The introduction of Christianity was hampered by the baneful influence of a secret society called the Kakian Union, to which pagans, Mahommedans and Christians indiscriminately attached themselves; and it has several times cost the Dutch authorities considerable efforts to frustrate their machinations (see _Tijdschrift van Ned. Ind._, fifth year). The total population is estimated at 100,000, including 12,000 Christians and 16,000 Mahommedans. The chief settlements are Savai at the north and Elpaputeh at the south end of the isthmus of Taruno. There was a Dutch fort at Kambello, on the west side of Little Ceram, as early as 1646.

CERAMICS, or KERAMICS ([Greek: keramos], earthenware), a general term for the study of the art of pottery. It is adopted for this purpose both in French (_céramique_) and in German (_Keramik_), and thus has its convenience in English as representing an international form of description for a study which owes much to the art experts of all nations, though "ceramic" and "ceramics" do not appear in English as technical terms till the middle of the 19th century.

The word "pottery" (Fr. _poterie_) in its widest sense includes all objects fashioned from clay and then hardened by fire, though there is a growing tendency to restrict the word to the commoner articles of this great class and to apply the word "porcelain" to all the finer varieties. This tendency is to be deprecated, as it is founded on a misconception; the word "porcelain" should only be applied to certain well-marked varieties of pottery. The very existence of pottery is dependent on two important natural properties of that great and widespread group of rocky or earthy substances known as clays, viz. the property of plasticity (the power of being readily kneaded or moulded while moist), and the property of being converted when fired into one of the most indestructible of ordinary things.

The clays form such an important group of mineral substances that the reader must refer to the article CLAY for an account of their occurrence, composition and properties. In this article we shall only deal with the various clays as they have affected the problems of the potter throughout the ages. The clays found on or close to the earth's surface are so varied in composition and properties that we may see in them one of the vital factors that has determined the nature of the pottery of different countries and different peoples. They vary in plasticity, and in the hardness, colour and texture of the fired product, through an astonishingly wide range. To-day the fine, plastic, white-burning clays of the south of England are carried all over Europe and America for the fabrication of modern wares, but that is a state of affairs which has only been attained in recent times. Even down to the 18th century, the potters of every country could only use on an extensive scale the clays of their own immediate district, and the influence of this controlling factor on the pottery of bygone centuries has never yet received the attention it deserves.[1]

_General Evolution of Pottery._--The primitive races of mankind, whether of remote ages or of to-day, took perforce such clay as they found on the surface of the ground, or by some river-bed, and with the rudimentary preparation of spreading it out on a stone slab if necessary and picking out any rocky fragments of appreciable size, then beating it with the hands, with stones or boards, or treading it with the feet to render it fairly uniform in consistency, proceeded to fashion it into such shapes as need or fancy dictated. Fired in an open fire, or in the most rudimentary form of potter's kiln, such pottery may be buff, drab, brown or red--and these from imperfect firing become smoked, grey or black. How many generations of men, of any race, handed on their painfully acquired bits of knowledge before this earliest stage was passed, we can never know; but here and there, where the circumstances were favourable or the race was quick of observation, we can trace in the work of prehistoric man in many countries a gradually advancing skill based on increased technical knowledge. For ages tools and methods remained of the simplest--the fingers for shaping or building up vessels, a piece of mat or basket-work for giving initial support to a more ambitious vase,--until some original genius of the tribe finds that by starting to build up his pot on the flattened side of a boulder he can turn his support so as to bring every part in succession under his hand, and lo! the potter's wheel is invented--not brought down from heaven by one of the gods to a favoured race, as the myths of all the older civilizations or barbarisms, Egyptian, Chaldean, Greek, Scythian, and Chinese have fabled, but born from the brain and hand of man struggling to fulfil his allotted task.

Formerly every writer on the history of pottery seemed to imagine that the very rudest pottery must have been the invention of Egyptian, Chinese or some other distinct race from which the knowledge radiated to all the other races of the prehistoric world. No conception could be more erroneous. Since the middle of the 19th century research has established beyond doubt that wherever clay was found men became potters of a sort, just as they became hunters, carpenters, smiths, &c., by sheer force of need and slowly-gathered tradition. The not yet exploded view that Egypt or Assyria was the special cradle of this art, and that the pottery of the Greeks and Romans directly descended from such a parent stock, cannot survive in view of the incontestable evidence that pottery was made by the prehistoric peoples of what we now call Greece, Italy, Spain and other countries, long before they were aware that any other peoples lived on the earth than themselves.

For centuries this simple hand-made pottery was hardened by drying in the sun, so that it would serve for the storage of dried grain, &c., but the increasing use of fire would soon bring out the amazing fact that a baked clay vessel became as hard as stone. Then, too, came the knowledge that even in one district all the clays did not fire to the same colour, and colour decoration arose, in a rude daubing or smearing of some clay or earth (a ruddle or bole perhaps), which was found to give a bright red or buff colour on vessels shaped in a duller-coloured clay--most precious of all were little deposits of white clay which kept their purity unsullied through the fire,--and by these primitive means the races of the dawn made their wares. On this substructure all the pottery of the last four thousand years has been built, for behind all Egyptian, Greek or Chinese pottery we find the same primitive foundations.

We now reach the beginnings of recorded history, and as the great nations of the past emerge from the shadows they each develop the potter's art in an individual way. The Egyptians evolve schemes of glowing colour--brilliant glazes fired on objects, shaped in sand held together with a little clay, or actually carved from rocks or stones; the Greeks produce their marvels of plastic form, and then, excited by their growing skill in metal work, turn the plastic clay into imitations of metal forms. These nations are overthrown, and the Romans spread some knowledge--only a tincture, it must be confessed--over all the lands they hold in fee; and from the Euphrates to the Atlantic, from Egypt to the Wall of Hadrian, they set alight potters' fires that have never since been extinguished. The Roman empire falls, and over Europe its pottery is forgotten along with its greater achievements; yet still pottery-making goes on in a very simple way, to be slowly revived and modified once more by the communities of monks, who, in later centuries, replace the Roman legions as the great civilizing influence in Europe. Meantime Egypt and the nearer East continued, in a debased form, the splendours of their glorious past, and glazed and painted pottery was still made by traditional methods. What part the Byzantine civilization and the Persians played during this obscure time, we are only just beginning to realize; but we now know that many interesting kinds of decorated pottery were made at Old Cairo, at Alexandria, at Damascus, in Syria, Anatolia and elsewhere (on which the later Moslem potters founded their glorious works), at a time when all over Europe crocks of simple red or drab clay, covered only with green and yellow lead-glazes, were the sole evidence of the potter's skill. What the Arab conquests destroyed, and what their breath quickened into life, we can only guess; but the fact is indisputable that with the Mahommedan conquests there came a time when the potter's art of the Occident reached its highest expression, and when methods and knowledge hitherto confined to Egypt, Syria and Persia were spread from Spain and the south of France to India--even, it may be, into China.

Meantime, in the farther East, the Chinese--the greatest race of potters the world has ever seen--were quietly gathering strength, until from their glazed, hard-fired pottery there emerged the marvellous, white translucent porcelain, one of the wonders of the medieval world.

With the dawn of the 15th century of our era, the state of affairs was practically this:--In European countries proper we find rudely fashioned and decorated wares in which we can trace the slow development of a native craft from the superposition of Roman methods on the primitive work of the peoples. The vessels were mostly intended for use and not for show; were clumsily fashioned of any local clay, and if glazed at all then only with coarse lead-glazes, coloured yellow or green; in no case above the level of workmanship of the travelling brick- or tile-maker. The finest expression of this native style is to be found in the Gothic tile pavements of France, Germany and England, where all the colours are due to the clays and there is no approach to painting. In the Moslem countries--including the greater part of Spain and Sicily, Egypt and the nearer East, probably even to the very centre of Asia--pottery was being made either of whitish clay and sand, or of a light reddish clay coated with a white facing of fine clay or of tin-enamel, on which splendid decorative patterns in vivid pigments or brilliant iridescent lustres were painted.

As early as the 12th century of our era this superior artistic pottery of the Moslem nations had already attracted the notice of Europeans as an article of luxury for the wealthy; and we may well believe the traditional accounts that Saracen potters were brought into Italy, France and Burgundy to introduce the practice of their art, while Italian potters certainly penetrated into the workshops of eastern Spain and elsewhere, and gathered new ideas. In Italy certainly, and in the south of France probably, efforts were continuously in progress to improve the native wares by coating the vessels with a white "slip" and drawing on them rude, painted patterns in green, yellow and purplish black. The increasing intercourse with Spain, in war and peace, also introduced the use of tin-enamel after the fashion of the famous Hispano-Moresque wares, and by the end of the 14th century a knowledge of tin-enamel was widespread in Italy and paved the way to the glorious painted majolica of the 15th and 16th centuries. From Italy and Spain, France and Holland, Germany, and finally, though much later, England learnt this art, and the tin-enamelled pottery of middle and northern Europe, so largely made during the 17th and 18th centuries, was the direct offshoot of this movement of the Italian Renaissance.[2]

During the 15th and 16th centuries Chinese porcelain also began to find its way into Europe, and by the whiteness of its substance and its marvellous translucence excited the attention of the Italian majolists and alchemists. The first European imitation of this famous oriental porcelain of which we have indubitable record was made at Florence (1575-1585) by alchemists or potters working under the patronage, and, it is said, with the active collaboration of Francesco de' Medici. This Florentine porcelain was the first of those distinctively European wares, made in avowed imitation of the Chinese, which form a connecting link between pottery and glass, for they may be considered either as pottery rendered translucent or as glass rendered opaque by shaping and firing a mixture containing a large percentage of glass with a very little clay. After the cessation of the Florentine experiments we know of no European porcelain for nearly a century, though the importation of Chinese porcelain had largely increased owing to the activity of the various "India" companies. The next European porcelain, made like the Florentine of glass and clay, was that of Rouen (1673) and St Cloud (1696); and during the 18th century artificial glassy porcelain was made in France and England largely, and in other countries experimentally. German experimenters worked in another direction, and the first porcelain made in Europe from materials similar to the Chinese was produced at Meissen by Böttger (1710-1712). During the 18th century not only was there a very large trade in imported Chinese and Japanese porcelain, but there was a great development of porcelain manufacture in Europe; and in every country factories were established, generally under royal or princely patronage, for the manufacture of artificial porcelain like the French, or genuine porcelain like the German. The English made a departure in the introduction of a porcelain distinct from either, through adding calcined ox-bones to the other ingredients; and this English bone-porcelain--a well-marked species--is now largely made in America, France, Germany and Sweden as well as in England.

By the end of the 18th century the risks and losses attendant on the manufacture of the French glassy porcelain had caused its abandonment, and a porcelain made from natural materials like the Chinese has since been generally made on the continent of Europe.

The older tin-enamelled wares--derived from the Hispano-Moresque and the Italian majolica--so largely made in France, Holland, Germany and elsewhere during the 17th and 18th centuries, met with a fate analogous to that of the French porcelain. Tin-enamelled earthenware is always a brittle substance, soon damaged in regular use; so that, when, in the middle of the 18th century, the English potter first appeared as a serious competitor with a fine white earthenware of superior durability and precision of manufacture, the old painted faience gradually disappeared between the upper millstone of European porcelain and the nether millstone of English earthenware.

The 19th century witnessed a great and steady growth in the output of porcelain and pottery of all kinds in Europe and the United States. Mechanical methods were largely called in to supplement or replace what had hitherto remained almost pure handicraft. The English methods of preparing and mixing the materials of the body and glaze, and the English device of replacing painted decoration by machine printing, to a large extent carried the day, with a great gain to the mechanical aspects of the work and in many cases with an entire extinction of its artistic spirit. Even the hand-work that still remained was largely affected by the growing dominance of machinery; and the painting, gilding and decoration of pottery and porcelain, in the first half of the 19th century, became everywhere mechanical and hackneyed. During the latter half of the 19th century another influence was fortunately at work. Side by side with the increasing mechanical perfection of the great bulk of modern pottery there grew up a school of innovators and experimentalists, who revived many of the older decorative methods that had fallen into oblivion and produced fresh and original work, in certain directions even beyond, the achievements of the past. The 20th century opened with a wider outlook among the potters of Europe and America. In every country men were striving once again to bring back to their world-old craft something of artistic taste and skill.