C7B83x
| Invert
| Zool.

Me se)

TO THE

|

CORAL GALLERY

(PROTOZOA, PORIFERA OR SPONGES, HYDROZOA,
| AND. ANTHOZOA),

IN

THE DEPARTMENT OF ZOOLOGY,
BRITISH MUSEUM (NATURAL HISTORY).

CROMWELL ROAD, LONDON, S.W.

WITH NUMEROUS ILLUSTRATIONS.

PRINTED BY ORDER OF THE TRUSTEES.
1902.
(All rights reserved.)

PRICE ONE SHILLING.

PRESENTED

LY

@he Trustees

OF

THE BRITISH MUSEUM.

a a ee

a
§

eo
2v5
7 ee
eae

~
=
ra

2+
=

oy ee eS
Ea

Se eee

bea

. faetetestcz mies —

ai

s
¢

? ’ Sy
wren lsraimabedt rege case Cline

Piel Se:

y a
Tee ES Faas

i '
a Mae ay = = at an 0 gos pwn ane pepe Bees = me

“amg yak wo
ANOUd 1SV3 NUNLIY

!
|
i
1
i
{

, = FS eee —— ee ee Be
¢ | oo =} §
x —

H| Luoqeg omnidog See dt mi
Mee 43 i a =: aa
@ (‘aLvateg) fe i) i te |
sty IE} — :
ef ee kyes Ysiy 21g 3 n S |
ar i wn §
— ul 2
W| =e
AzeTTeg Tous
SS CLES ps HEF A BIR pe SRE 2 fa eee OD se OS TE po OE FG 1 IT ho il
wo Oat Bare | So

Bi hes Man HGrwed CGGGT eee Eeerd MmnneT Vimwen i

Red —

‘—ooee |

(uoory shawasvg Ng ) 3 ;

WoeYy sey, i ci a 3 |

: | AB i |

Bek BSB \ PT Ae oe re meee ere newer ee oe noe rhe es ee ae. ne ee ida se See Hines = ma = |

QL oe,
377 Ra!

C7Bs3~x Ne
Bony ect. Ge ED
Zool,

PORAL GALLERY

(PROTOZOA, PORIFERA OR SPONGES, HYDROZOA,
AND ANTHOZOA),

IN

TE DEPARTMENT OF ZOOLOGY,

BRITISH MUSEUM (NATURAL HISTORY),

CROMWELL ROAD, LONDON, S8.W.

WITH NUMEROUS ILLUSTRATIONS.

SE M\THSONIAiy
SEP 23 1086

PRINTED BY ORDER,OF ¥
Lote
1902. —

(All rights reserved.) Cy

emi
- — a

BRITISH MUSEUM (NATURAL HISTORY) oa

2 ‘ 5 ee ae Studies (Private) Studies ( Private.) : ©
: Co - ae " ——<—<—a TT OY (eee een = xo nnn ney |
f : ole - | mae ‘ y = B= \
: ‘ t . a] D H }
oy ag | | | : ( | = |
ie ds | | ay os g 8 |
t ' f ye b | ’ ; 3 a & x

‘¢ A ieee oie ie ) 5 ee 2 We J2 sz og :

| a 1 9 i © a ies] 7) ¢ + 23 - : Go poo!

[gad FF oat i = XS oe ) a ae re
H { Pier © Ee © 2 i) | a = {
: op S 4 fy rm S bt i
i 3 © ic Fi rs = S aif 8
: | roe © A Dn 77) 3 ra i=) % ce ! 3 '
oe oe ( @ = = Re ei a © | ye
{ ‘AQ | 7) a Pa om iS r | :
: g ~ ' f C = a a i z 8 4
° H ce = 3 | @&
i fo) x r: fy PX | = i
| PE a . ‘eo
; 2 4 | K
i = = >
7 i! allety
i| =s =: | oo)
Bin |
: re BI ; i
: = a

yn

cesta Tn To
al |
i. British Ht

alll
Vertebrates Bird Gallery

EAST WING

WEST WING
Palz ontology)

(Recent Zoology.)

——

Tye Dawserrietp Perms C2 Lr Lonvon.

* =
oe Pare pe oe ty wat. fi
oe a. : ; 5
ars on) i “Gree eo (St
4% ial > a) : ~ n , fi
. ‘ : " : ~ ad ae
‘ i : : 7 :
Ps >a?
- 14
a
s *

LONDON :
PRINTED BY WILLIAM CLOWES AND SONS, LIMITED,
DUKE STREET, STAMFORD STREET, S.E., AND GREAT WINDMILL STREET, W.

i Sg ‘
a i. Shy,

i : \

on: 2a
; cou SBR ig. |
hUEEUN IAN OTT! Tae

; vias ©
“, x \ ;
PUT 5 & a

PREFACE.

THE Coral Gallery, the contents of which are briefly described in
the following pages, is a long narrow corridor situated between the
Bird Gallery and the series of galleries on the north side of the
building, being interrupted by three cross-passages between the
galleries referred to. The collections exhibited in this gallery
include not only the objects commonly recognised as Corals, but also
other lower types of animal life scientifically known as Hydrozoa,
Porifera and Protozoa, which include jelly-fish and their allies,
sponges, and microscopic organisms such as Foraminifera and
Radiolaria, which in the remote past have played an important
part in the formation of the chalk and limestone rocks of the
earth’s crust. In giving an account of such objects as these it is
difficult to avoid the use of many scientific and technical terms, but
an endeavour has been made to make the text as comprehensible as
possible to the general public. Much care has been bestowed upon
the selection and preparation of the numerous illustrations, many
of which are entirely new. The part of the Guide referring
to Protozoa, Porifera and Hydrozoa has been prepared by Mr. R.
Kirkpatrick and the description of the Anthozoa by Mr. F. J. Bell.

In conclusion, thanks are due to Messrs. F. Warne & Co., Messrs.
‘Cassell & Co., Messrs. Macmillan & Co., Messrs. A. and C. Black,
and the Royal Society, for kindly allowing the use of illustrations
in various works published by them.

E. Ray LANKESTER.

TABLE OF CONTENTS.

=a
PAGE

PROTOZOA OR SIMPLEST ANIMALS .. a ae oe oc ao ally)
Introduction ae 30 ar ae a as be Ks 1
Gymnomyxa or Rhizopoda 0 ae a Be a a3 3)
Foraminifera or Reticularia cE ac at BA aS ae 7
Corticata or Infusoria 3 ae - ac as ae is 14
PORIFERA (Sponges)... ce e: 8 * Be Ae .. 20-37
Introduction ~ ss a fs fs us as fs 20
Classification a x 33 ee Ag = - a3 23
Calcarea!(Calcareous sponges) .. E es hs ie 25
Silicea (Siliceous sponges) a ot ee x Ae Be 24
Demospongiz or common sponges ef a a a +3 29
HypDR0zOA a Fr se a3 be on S6 srs .. 38-66
Introduction a 5 Fc a as He Be aie 38
Hydroida (Hydroid zoophytes) .. Ey: a A A 2: 40
Hydrocorallinz (Coral-like Hydrozoa) .. we a es re 47
Meduse (Jelly-fish) Bt oe fe 5 x x ‘ 54

ANTHOZOA (Sea-Anemones, Stony Corals, Bark Corals, etc.) Se .. 67-71

GUIDE TO THE CORAL GALLERY.

—_-o2—_

PROTOZOA OR SIMPLEST ANIMALS.

INTRODUCTION.

THE majority of the Protozoa are extremely small objects, being High Wall
in many cases invisible or barely visible to the naked eye. Conse- ee x
quently, excepting in certain instances, diagrams and models are Gallery.
exhibited in place of specimens.!

The Protozoa are essentially composed of one “ cell.” The word
“cell” was originally used to describe a vegetable cell or vesicle with
its walls and fluid contents, just as we speak of a bottle of wine ;
but now the term is used for the minute corpuscles of protoplasm
or living substance which build up animal and vegetable structures.

The Protozoa stand in contrast with all the rest of the Animal
Kingdom or Metazoa, the latter being composed of many cells of
different kinds united into a commonwealth organised on the
principle of division of labour. In the figure of Hydra (p. 39), for
instance, we see a sac composed of two layers of “cells,” those of
the inner layer being concerned in the digestion of food, those of
the outer having protective and sensory functions ; here each cell is
subordinate to the community of cells and cannot live independently.

Many Protozoa form colonies, but the individual cells resemble each
other, and each cell is independent of the others.

By way of introduction to the subject, a brief description of a
Protozoon is given below.

Amaba proteus, or the Proteus Animalcule (Fig. 1), resembles
a tiny blob of whitish jelly about 1, of an inch in diameter ; it is
commonly found at the bottom of ponds on the ooze, where it creeps
about in search of food.

The Ameba, observed under the microscope, usually seems
globular and motionless at first, but presently beads appear on the
surface, some of which enlarge and flow out in the form of finger-like

1 The diagrams and models exhibited in the Case are referred to in the
text as ‘‘ Plate}’ and,‘‘ Model,’’ with their appropriate number.

kK

High Wall
Case

EK. end of
Gallery.

2 GUIDE TO THE CORAL GALLERY.

lobes. ‘The lobes are termed ‘“ pseudopodia” (seudos, false or
apparent ; yous, foot), because they enable the animal to move
about. ‘In the continual extension and branching of one or more
of the chief pseudopods,” writes Professor Leidy, “the Amaba
progresses more or less rapidly, the body appearing incessantly
to exhaust itself in the continual growth and elongation of the
pseudopods and in the production of new ones, while it is as

Fic. 1:

Ameba proteus, the Proteus Animalcule. Figure on left, small specimen, mag-
nified 250 diameters. Figure on right x 200. mn, nucleus; ¢ v, contractile
vacuole; f, foreign bodies; p, pseudopods. Arrows indicate direction of
streaming of pseudopods and of motion of the animal. (After Leidy.)

incessantly replenished by the contraction and melting away of
pre-existing pseudopods.” The little creature is continually chang-
ing its shape, and hence Rosel, who discovered it in 1755, called it
“the little Proteus,” after the monster of the fable.

When the Amwba comes in contact with a Diatom, Desmid, or
other object suitable for food, it envelops and ingests it, and, in
due time, casts out the indigestible débris.

PROTOZOA OR SIMPLEST ANIMALS. 3

Food may be taken in and the remains ejected at any point of High Wall
the body, but sometimes only over more or less definite areas. The oe aot
body of the animal is usually crowded with food-balls, shells of Gallery.
Diatoms, cells of green algae, &c.

The protoplasm of the body, with the exception of a thin, clear,
outer layer, is granular ; at one part (Fig. 1) is seen a discoid, denser
portion of protoplasm, known as the “nucleus.” There is also
present in the interior of the body a clear spherical vesicle—the
* contractile vacuole ”’—which slowly expands and rather suddenly
collapses and disappears, reappearing at the same spot and going
through the same cycle. The contractile vacuole is probably an
organ for the excretion of waste products. The animal reproduces
itself by dividing into two, this process being preceded by division of
the nucleus, each half of the Ameba becoming a distinct individual.

CLASSIFICATION.

The Protozoa are divided into two great sections—the GyMNo-
Myx or RHIzOPODA, and the CorticaTa or INFUSORIA.

In the first section, the protoplasm of the cell is homogeneous
throughout, but in the second the superficial layer is firmer than
the more fluid interior portion.

The Gymnomyxa, in their adult phase, move about and obtain
their prey by means of pseudopods. The Corticata are provided
with flagella or cilia. A classification of the Protozoa (after Prof.
Lankester, HLneyc. Britannica) is given in the “ Explanation of
Plates” in the Case.

GYMNOMYXA (RHIZOPODA).

For simplification, the Gymnomyxa are here divided into four
groups :—

I. Logzosa, with lobose pseudopods.

II. Hurrozoa, with fine radiating pseudopods.

II]. ForRAMINIFERA, in which main trunks of pseudopods branch
out into a fine network, and with a shell usually composed of carbonate
of lime.

TV. Rapronari, with a “central capsule,” with fine radiating
pseudopods, and usually with a shell of silex or horny acanthin.

B 2

High Wall
Case

E. end of
Gallery.

4 GUIDE TO THE CORAL GALLERY.

LOBOSA.

The Loposa, or Gymnomyxa with lobose pseudopods, may be
without shells, as Ameba (see Plate III. and Model 1 in the Case),
or they may be enclosed in a shell, as, for example, Diflugia
pyriformis (Model 2) and Difflugia acuminata (Plate III. in Case),
in both of which the shell is composed of cemented sand-grains.
The shelled forms creep about with the shell uppermost and with

Fia. 2.

\
\

- ye eS

Actinophrys sol, the Common Sun-Animalcule. The large globule
projecting from the surface is a contractile vacuole. Magnified
500 diameters. (After Leidy.)

the pseudopods emerging from the aperture below. The Lobosa
live, for the most part, in fresh water, damp moss, etc.

The Mycrrozoa, or Funcus Anas, which may be con-
veniently referred to here, are, by some naturalists, regarded as
vegetable organisms. In dealing with the lowest organisms, it is
often difficult to determine definitely their true position in the
kingdom of life, whether they are to be regarded as members of the

~

PROTOZOA OR SIMPLEST ANIMALS. 9)

animal or vegetable kingdom, or as being inan intermediate position. High Wall
In some phases of thee life-history, Mycetozoa exhibit characters oe et
attributed to vegetable organisms; in other phases, again, they Gait

Fic. 3.

Clathrulina elegans, the Latticed Sun-Animalcule.
Maguified 350 diameters.
resemble undoubted animal organisms. One of the best known
forms is Fuligo septica, which creeps over the surface of tan-pits.
The creeping “plasmodium” develops masses of cysts known as

High Wall
Case

E. end of
Gallery.

6 GUIDE TO THE CORAL GALLERY.

“flowers of tan.” The cysts rupture and liberate Ameba-like
spores (flagellule), which fuse together to form a plasmodium.

LDidymium, one of the Mycetozoa, is figured in Plate II. in the
Case.

HELIozoA OR SuN ANIMALCULES.

The Sun Animalcules are more or less spherical in form and pro-
vided with fine ray-like pseudopods. They mostly inhabit fresh water.
Actinophrys sol, the Common Sun Animalcule (Fig. 2), lives

Fig. .4.}

Miliolina tenera, one of the Imperforate Foraminifera. Young
living animal with expanded pseudopods. A nucleus is seen
in the innermost chamber. Magnified. (After Max Schultze.)

arhongst weeds in ponds. “It commonly appears as a globular,
hyaline, foamy, or vesicular body, bristling with delicate rays, and
suspended almost stationary in the water” (Leidy). The total
diameter is about 54, of an inch. The body generally contains, in
addition to the central nucleus and the contractile vacuole, numerous
vacuoles and food-balls: the contractile vacuole is usually seen
emerging from a point on the surface, bursting, and reappearing at
the same spot (Model 3). Actinophrys swims by means of its
flexible pseudopods, and when one of these touches some organism,
the latter is drawn towards the body and engulfed. Well might

' From ‘‘ Encyclopedia Britannica.” }

PROTOZOA OR SIMPLEST ANIMALS. 7

Joblot, who, in 1754, first discovered it pirouetting about in an High Wall
infusion of celery, speak of it as “the most extraordinary fish one [ase
5 ; ; : E. end of

could imagine.” A continual streaming of the protoplasm rendered Galiery.
visible by the granules in its substance is continually proceeding up ‘
and down the pseudopods. The little organism reproduces itself by
dividing into two (Model 4).

Actinospherium eichornii (see Plate V.in the Case) has a spherical
body with a well-defined outer zone of large vacuoles; this form,
which is also abundant in ponds, somewhat resembles a giant Sun
Animalcule, being about five times the size of Actinophrys.

Rhaphidiophrys elegans may be either solitary (Model 5), or may
form colonies in which several of the spheres are joined by bands
(Model 6); numerous slender curved spicules of silex abound in
the surface layer of the body and pseudopods.

Clathrulina elegans (Fig. 3), which lives in ponds and ditches,
may be compared to a Common Sun Animaleule enclosed in a
latticed sphere of silex supported on a slender stalk; the diameter
of the shell is about ;35 inch, and the length of the stalk about
tyy inch. See Model 7 in the Case.

FORAMINIFERA OR RETICULARIA.

The majority of the Foraminifera form a shell of carbonate of
lime ; in some, the shell is composed of cemented sand, mud, or
sponge spicules, and, in a few species, of membrane or silex. The
series of Foraminifera mounted on slides is arranged in ten families
according to Mr. H. B. Brady’s classification, an enlarged figure
being placed below each slide. The classified series is preceded by
an introductory account of the group. The small plaster models on
steps and on the floor-shelf represent selected types, both living
and fossil.

When the skeletons of Foraminifera were first discovered, they
were supposed to be the shells of tiny Cephalopods or other Molluscs.
Great was the sensation in the scientific world when, in 1835,
Dujardin found, from observation of the living animals, that the
builders of these complicated shells consisted simply of apparently
structureless protoplasm, which extruded root-like trunks of branch-
ing and anastomosing threads whereby the creatures crept along
(Figs. 4,5). Accordingly he removed these organisms from the
Mollusca and placed them in a new group, Rhizopoda (rhiza, root ;
pous, foot).

Foraminiferal shells either have only one or a few main apertures

/ l/) Wi / H | | 11}
LTE EL VA AK

Polystomella, one of the Perforate Foraminifera, showing trunks of pseudopods
emerging from the shell. Magnified 200 diameters. (After Max Schultze.)

Fic. 6.

A section of Nummulitic Limestone from a Himalayan Peak 19,000 feet above
sea-level. Magnified 40 diameters.
In the upper left corner of the plate are vertical sections (willow leaf pattern),
and near the upper right corner a section, in horizontal plane, of Nummuvtlites.
Distributed over the field are numerous sections of Miliolina, Rotalia, Textu-
laria, &e.

To face p. 9.

PROTOZOA OR SIMPLEST ANIMALS. 9

(Imperforata, Fig. 4), or have, in addition to the main aperture, the High Wall
wall of the shell perforated by numerous pores (Perforata, Fig. 5). ee ee
Calcareous imperforate shells (see Family II.) have an opaque white Gallery.
porcellanous appearance, and perforate shells, in their early stages,
a vitreous appearance (Families V. to X.). The shell may consist of
one chamber (Lagena, Family VII.), or of many, arranged in linear,
spiral, or concentric series, or on each side of a middle line.

In Globigerina, Rotalia, &c. (Family VIII. and IX.), all the
chambers of the “rotaliform” spiral are visible from above, but

Hires). 7:

Shells of Globigerina, showing lower and upper surface. Magnified.

only the last coil from below. In Mummulites (Family X. and
Introductory series) the last coil of the spiral wholly encloses all the
preceding coils.

Although many of the specimens in the Case are very small, yet,
with the aid of the diagrams, the shape can frequently be made out ;
in some species the shells attain to relatively immense proportions,
as Cycloclypeus carpenterti (Family X.), from Borneo, with a thin
discoid shell over two inches in diameter.

The Foraminifera have played an important part in forming

High Wall
Case

EK. end of
Gallery.

10 GUIDE TO THE CORAL GALLERY.

the rocks (chalks and limestones) of the earth’s crust, and at the
present time are covering millions of square miles of the ocean floor
with a pinkish-white mud or ooze, formed chiefly of their skeletons.
The shells of Globigerina bulloides (Fig. 7 ; and specimens and figures
in Introductory series), a species which lives at the surface of the
ocean, form a large proportion of the ooze, which is hence termed
“ Globigerina Ooze.” .The piece of dark-coloured Tertiary Nummu-
litic limestone (Fig. 6) exhibited in the Case, formed part of the
débris from the summit of a Himalayan peak 19,000 feet above the
sea-level. The occurrence of this ancient sea-floor in its present
position affords clear proof of the elevation of the peak within—
geologically speaking—comparatively recent times.

The large plaster models of Biloculina illustrate “ dimorphism,”
a phenomenon now found to be of frequent occurrence in Foramini-
fera, and attributed to alternation of generations.

One of the vertical sections shows a large central chamber
(megalospheric form), and the other shows numerous small ones
(microspheric form). Parallel series of fossil Nummulites (see
Introductory series and Family X.) are often found together in a
stratum, disks with small central chambers occurring along with
usually smaller disks with large central chambers ; formerly the two
kinds were regarded as different species, but are now considered to be
different forms of one and the same species.

RADIOLARIA.

The characteristic feature of the Radiolaria is the presence of a
membranous ‘‘ central capsule” dividing the body into two zones, an
intra-capsular zone including the nucleus, and an extra-capsular
whence the pseudopods radiate. The vast majority form a skeleton
of silex or of acanthin, a horny organic material; a few species
are without a skeleton.

The Radiolaria live in the warmer waters of the ocean, mostly at
or near the surface, but some species exist only in the deeper zones.
Over vast areas in the tropical Pacific and Indian Oceans, and at
depths of about 3,000 fathoms, the ocean floor is composed of an
ooze chiefly made up of the skeletons of Radiolaria, and hence
termed Radiolarian Ooze. Certain rocks, as, for instance, Barbados
Earth, are largely or almost entirely composed of Radiolarian
skeletons.

When floating alive at the surface, Radiolaria are often richly

PROTOZOA OR SIMPLEST ANIMALS. i

coloured with crimson, blue and yellow tints, and have been well High Wall
termed “gems of the ocean.” Their skeletons assume an endless ree of
variety of beautiful and curious shapes, such as spiny latticed Gallery.
spheres, rings, beehives, &c. The Radiolaria, of which about

4,000 species have been described, are primarily classified according

to the structure of the central capsule, the shape of the skeleton

tending to conform, more or less, to the shape of the latter.

Professor Haeckel divides the group into four Orders :—

Hig. .8:!

Haliomma wyviliet. Magnified 200 diameters. (After Wyville Thomson.)

I, SPUMELLARIA (Fig. 8), and see Plate VII. and Models 9-12
in the Case, with spherical central capsule uniformly perforated by
pores. Here the skeleton is typically formed of a latticed sphere or
of several concentric latticed spheres united by radial beams which
do not penetrate the central capsule, and with radiate spines.

‘ From ‘‘ The Voyage of the Challenger—Atlantic.”

High Wall
Case

E. end of
Gallery.

12 GUIDE TO THE CORAL GALLERY.

Spongosphera (Model 12) has three spheres, the outermost consisting
of a spongy reticulum ; the fine smooth spines in this model represent
pseudopods, but the pseudopod rays are beaded in the other models.
Spongosphera streptacantha, which is common on the surface of
warm-temperate and tropical seas all over the world, is about
go of an inch in diameter.

II. AcanTHarta (Fig. 9, and Model 13), with spherical porous

Fig. 9.)

\ Wl |
SS \ X ah
‘ NA KIN GF
= WN \ A = = | x s S Vika 4
SS gy / EB Saber Ss K
SSN CER yy > Y p
SSX f aK } | Pe yy 5 ZY
rs QB Yes “a
{i > A AN 4 Zs B 1 I N

XK

Xiphacantha murrayana. Magnified 100 diameters. Skeleton only.
(After Wyville Thomson.)

central capsule, with skeleton of “acanthin,” constructed of 20
radiate spines proceeding from the centre, and always arranged in |
fours according to a definite law known as “ Miiller’s Law.” The
idea of a terrestrial globe with its parallels helps one to realize the
plan; thus Haeckel calls the five fours equatorial, tropical and

‘From ‘‘The Voyage of the Challenger—Atlantic.”

PROTOZOA OR SIMPLEST ANIMALS. i183

polar. The radiate spines give off horizontal or tangential spines or High Wall

plates, which may remain separate (Fig. 9) or may fuse to form aoe ae
latticed sphere (see Model 13 of Dorataspis diodon in the Case). Gallery.

III. Nassennuarta. The central capsule is conical, and perforated

Fic. 10.2

Eucyrtidium cranioides. Entire animal as seen in the living
condition. Magnified 150 diameters. (After Haeckel.)

only by a large opening in the basal region. Hucyrtidium (Fig. 10) and
Dietyopodium, see Models 14, 15 in Case, are beehive-shaped with three
segments. The yellow balls situated on the pink central capsule repre-
sent a symbiotic Alga, commonly found associated with Radiolaria.

' From ‘‘ Encyclopedia Britannica.”

High Wall
Case

E. end of
Gallery.

14 GUIDE TO THE CORAL GALLERY.

Eucecryphalus schultzei has only two segments, the lower being
expanded out, and the central capsule is lobed ; see Model 16 in Case.

IV. PuHaroparta (Models 17, 18), with a double-walled central
capsule with a few large orifices, and surrounded by dark brown
pigment. The skeleton of Awlosphera (Model 17) is formed entirely
of tubes of silex, which join to forma spherical lattice with triangular
meshes, a tube with verticils of spines radiating from each node.
This species, which lives at the surface in the Mediterranean, has a
large shell ,4, of an inch in diameter.

Aulacantha (Model 18) has a skeleton formed of hollow siliceous
tubes of two kinds, viz., radiating spines and loose needles arranged
tangentially on the surface.

CORTICATA OR INFUSORIA.

If any animal or vegetable substance be allowed to remain in a
vessel of clear water exposed to the air, in a short time tiny specks
will be seen swimming about. ‘The organisms appearing in these
infusions were termed Infusoria or Infusions Animalcules. The
organic matter has simply served as nutriment to the germs of
these Animalcules previously existing in the water or in the air.
Infusoria abound in fresh and stagnant water and also in the sea.

The organisms grouped under this name differ from the Gymno-
myxa, usually in having, in their adult phase, flagella or cilia in place
of pseudopods. A cilium isa hair-like organ which can only bend
and straighten itself, and which only acts in unison with other
cilia. A flagellum acts independently, and with a lashing to and
fro movement.

The Corticata may be roughly divided into four groups: Sporo-
zoa, Flagellata, Ciliata, and Acinetaria.

SPOROZOA.

The Sporozoa are parasitic organisms which live on the juices of
other animals, and accordingly, in their adult phase, are devoid of
cilia or flagella, having no need for these organs.

Porospora (Gregarina) gigantea, see Plate VIII. in the Case, from
the intestine of the Lobster, has an elongated worm-like body with
two segments. The elongated body becomes a spherical cyst, the
contents of which break up into thick coated spores ; on the rupture
of a spore, an Ameba-like body is liberated, which develops into a
Gregarina.

PROTOZOA OR SIMPLEST ANIMALS. 15

FLAGELLATA.

The FLAGHLLATA are Corticata in which the cell-body is provided High Wall
with one or a few flagella. The cell may be solitary (Fig. 114), or Case

Ea : : a. E. end of
may be joined with others to form colonies (Figs. 118, ¢). Gallery.

Hie> i.

=p NAO A
\(c) ap
ae

Flagellata. a. Cercomonas crassicauda, a one-celled Flagellate. (x 400).
B. Gonium pectorale (x 325). oc. Volvox globator with daughter and grand-
daughter colonies (x 55). (After Carter.) vp. Surface view of Volvox
showing cells in hexagonal spaces in common jelly; n, nucleus; ev, con-
tractile vacuole. Very highly magnified. (After Biitschli.) 4. Vertical
section of wall of Volvox (x 800). a, pairs of flagella. (After Cohn.)

Volvox globator (Figs. 110, D, E), and Plate [XA. in the Case, occurs
at times in great abundance in ponds, even to the extent of giving a
green colour to the water. The little organism, which is about 1, of
an inch in diameter, looks like a tiny green speck moving about in

High Wall
Case

EK. end of
Gallery.

16 GUIDE TO THE CORAL GALLERY.

the water (in a tumbler). On being magnified, the speck is seen to
be a spherical sac uniformly dotted with green points and progressing
by a peculiar revolving movement. Frequently the sphere con-
tains several green “daughter” spheres, and these, again, “ grand-
daughter” spheres. The wall of the sphere is composed of a layer
of cells (the separate green points), each provided with two flagella.
The cells are embedded in a common jelly, each cell in a separate
compartment, but connected with its neighbours by radiating strands.
The outer surface of the sphere is covered with a pellicle through
which the pairs of flagella penetrate, and the interior is filled with
fluid in which daughter colonies may often be seen revolving. In
addition to a nucleus and contractile vacuole, the body of each cell
contains green chlorophyll granules. The daughter colonies inside
the sphere escape in due time by rupture of the outer wall of the
parent. Volvox is generally regarded by
botanists as a plant.

Gonium pectorale (Fig. 11B),a colonial
organism belonging to the same family
as Volvoz, forms flat plate-like colonies
composed of sixteen cells, each cell
having a pair of flagella at its upper
end. In one large section of Flagellata
the cell is provided at its upper end
with a collar, so the flagellum appears
Noetiluca miliaris, the Phos- to arise from the floor of a_ basin.

EO ebioule, ue Codosiga cynisca (Plate IX. in the Case)
forms a branching colony. Some of the
collared Flagellates secrete a horny cup or receptacle for the cell,
as in the solitary Salpingeca napiformis (Plate [Xa. in the Case),
which forms a stalked horny cup containing the collared flagellate
cell. Proterospongia haeckeli is a colonial form with Amaba-like
cells in addition to collared cells, all sunk in a common test.
The ancestor of the Sponges, which are unique among the Metazoa
in possessing collar-cells, was probably a collared Flagellate. The
Mail Coated Flagellata have a flattened body, with a longitudinal
groove from which a large flagellum projects, and usually, in addition,
a transverse groove with a flagellum lying in it. These forms are
mostly marine and often phosphorescent. Some species which have
a cuticular shell of cellulose, and which contain chlorophyll, are
claimed by botanists as plants, but there are closely allied species
without the cellulose investment or the chlorophyll. Ceratium tripos

re 12:

PROTOZOA OR SIMPLEST ANIMALS. ay

(Plate X.in the Case) has a flat triangular body with a spine at each
angle. The two grooves form an inverted T-shape, the vertical bar
being very broad. The presence of cilia in the transverse band in
Plate X. is incorrect, there being simply a single flagellum lying in
the groove.

Ceratium is phosphorescent, and in the open ocean is often united
into chains of two to twenty individuals.

Noctiluca miliaris (Fig. 12) is a little peach-shaped organism
about ;4, of an inch in diameter. A thick transversely-striated
“big flagellum” springs from the bottom of a deep groove on one

Vorticella nebulifera, a colonial Bell-Animalcule.
(Magnified). ev, contractile vacuole.

side of the body. Near the groove is the mouth leading into a
cylindrical throat, in which is placed a second and smaller flagellum.
The body is invested by a firm cuticle, and the protoplasm in the
interior is vacuolated. See Plate XI. in the Case.

Noetiluca is highly phosphorescent, the light emanating chiefly
from the protoplasm just beneath the cuticle.

Marine phosphorescence is sometimes due entirely to the presence
of myriads of Noctiluce, which may be present in such abundance

C

High Wall
Case

KE. end of
Gallery.

High Wall
Case

E. end of
Gallery.

18 GUIDE TO THE CORAL GALLERY.

as to give a reddish colour to the surface of the sea in daytime. In
the Persian Gulf, a richly pigmented variety occasionally forms on
the surface of the sea brilliant scarlet bands, which extend for many
miles.

CILIATA.

The members of this group are characterised by the presence of
cilia on the surface of the body. These organs may form a spiral coil
round the anterior end of the body in relation to the mouth, or they
may be distributed over the whole or part of the surface of the body.
Carchesium polypinum (Plate XII. in the Case), which belongs to the
eroup of “ Bell Animalcules,” occurs in ponds in the form of bluish

he

Stentor polymorphus, the Trumpet Polypus. (Magnified).

mucilaginous filmy patches on fresh-water plants, pieces of wood, &c.
The branching fan-shaped colony is highly contractile, and shrinks
into a spherical ball on being alarmed. Each individual has a
bell-shaped body seated on a stalk. The cilia, which form a
spiral fringe round the anterior end, set up a vortex in which food
particles are carried through the funnel-like mouth and gullet
situated inside the rim, and thence into the interior of the body.
Vorticella nebulifera (Fig. 13) also forms colonies ; the figure shows
the individuals in various phases of contraction. Some species of
Bell Animalcules are solitary and do not form colonies. Séentor

PROTOZOA OR SIMPLEST ANIMALS. 19

polymorphus, the Trumpet Polypus (Fig. 14), has a funnel-shaped High Wall
body of green colour, about 51; of an inch in length, and is usually Case
2 : . end of
to be found singly or in groups attached by the narrow end to Gajery.
duck-weed, sticks, &c.; when swimming, the organism changes its
shape considerably, becoming ovoid or
pear-shaped. The cilia are uniformly
distributed over the whole surface, but
form a spiral fringe of long cilia round
the anterior edge. See Plate XIIA., 2,
in the Case.

Paramecium aurelia, the Slipper
Animalcule (Plate XIIa., 1, in the
Case), has an oval flattened body with
cilia. uniformly distributed over the
whole surface. Stylonychia (Fig. 15)
has cilia only on the under surface of the
flattened body; the thick spine-like organs
are peculiarly modified cilia by means of
which the organism can stalk about.

Hires, 15:

ACINETARIA.

The body, in this group of Corticata,
is provided with tentacle-like organs in
place of cilia and flagella. Dendrosoma
radians (Plate XIII. in the Case) is a
fresh-water Infusorian of rather large
size, attaining a height of +45 of an inch.
A fixed stolon gives rise to branching Stylonychia mytilus, the Mussel-
trunks; each branch terminates in ‘Animalecule. Magnified 150
numerous suctorial knobbed tentacles, ‘iameters. a, mouth; b, con-

: P fi f tractile vacuole; c, nucleus.
which act by plunging into the bodies
of their prey and sucking up the protoplasm. In the young stage,
Dendrosoma is free and provided with cilia, which disappear when
the animal becomes fixed.

Q
to

High Cases
I.-VI. and
Table Cases
1 and 2 A, B.

20 GUIDE TO THE CORAL GALLERY.

PORIFERA [SPONGES |.

(The High Cases are indicated by Roman numerals and the shelves of the
same by Arabic numerals. ]

INTRODUCTION.

The term “sponge” is popularly associated solely with the soft
elastic bath sponge, but a glance at the Cases will show that, in
zoology, the word has a much wider meaning, some “sponges”
being of stony hardness, others leathery, others again like spun glass.

In life, the bath sponge is tough and fleshy, and covered with a
black skin (Case I., specimen in fluid). A section (Fig. 18) shows
a light-coloured flesh in which no trace of the horny skeleton,
commonly known as the sponge, is apparent ; to obtain this the
skin and flesh are macerated off, leaving the more resistant SKELETON.

It would be instructive here to notice the glassy skeleton of
Euplectella aspergillum, or Venus’ Flower-Basket (Cases III. 2), and a
complete specimen of the same in fluid (Table Case 24) ; here again
the skeleton is concealed by the soft tissues. The dried specimen of
Euplectella imperialis (Case III. 3) shows the fluffy-looking soft
tissues above and the denuded skeleton below.

Many specimens, especially those in Cases IV.-VI., do not
materially differ, excepting in colour, from their appearance in life.

The position of Sponges in the Animal Kingdom is above the
Protozoa or Simplest Animals and near the Ceelentera (Zoophytes,
Corals, &c.).

To give some idea of the structure of a sponge, a brief account is
given of Halichondria panicea, the Crumb-of-Bread Sponge, common
round the British coast (Case IV. 3).

This sponge forms yellow or greenish crusts on rocks, or shapeless
masses round the stems of sea-weeds. The surface of incrusting
specimens is usually covered with crater-like orifices termed oscules.
On closely observing living specimens in a large vessel of sea-water,
currents, rendered visible by débris, will be seen coming out of the
oscules ; a little indigo or carmine will serve to render the currents
still more apparent.

HitGeele

Aphrocallistes vastus, a Dictyonine Sponge. (One-seventh natural size.

To face'p. 20.

PORIFERA [SPONGES]. 21

The origin of these sponge fountains had always been a profound High Cases
enigma, which Dr. Grant quaintly compared to that of the then Le
mysterious sources of the Nile. In 1825 the above-named zoologist 1 and 2 a. x.
observed small particles being carried by currents through minute
PORES in the general surface of the Halichondria (Figs. 2, 3B); and
on account of the presence of these pores, he gave the name Porifera
to sponges. So much for the entrance and exit of currents: to
ascertain their complete course and their cause, it is necessary to cut
very thin slices of the sponge (Fig. 3). The pores (Fig. 3B) lead
into spaces and channels, which are more or less branched, and which
finally arrive at the outer surface of groups of spherical cavities
termed flagellated or whip chambers, each 51, of an inch in

hie 2.

Halichondria panicea (after Dr. Grant). a, pores; e, oscule; f, ova. The out-
ward arrows show the currents escaping by the oscules; the inward ones
water entering the pores.

diameter, and with minute orifices in their walls. The whip
chambers open each by a comparatively large orifice into channels or
spaces ; these join with others to form larger and larger canals,
which terminate in an oscule. The whip chambers are lined with
“ collar-cells ” (Fig. 3c), each of which is provided with a flagellum
or whip and a hyaline collar; the beating of the whips sets up the
currents, which bring in food-particles and oxygenated sea-water, the
used-up water and débris being driven out through the oscules.
Food-particles are taken up bodily by the cells lining the walls of
the canals and by the collar-cells ; but not much is known on this
subject at present. The CANAL systEM from the pores to the
whip chambers is termed “in-current,” and that from the whip
chambers to the escules “ out-current.”

High Cases
I-VI. and

Table Cases
land 2a, B.

>

22 GUIDE TO THE CORAL GALLERY.

Fic. 3.

Sa

A

B

=

. Halichondria panicea. Vertical section x 100. Partly diagrammatic.
a, oscule ; b, pores; ec, whip chambers. 8. Dermal membrane or skin with
pores x 100. c. Whip chamber x 1,600 (after Vosmaer). p, Skeleton
spicule x 100.

PORIFERA [SPONGES]. 23

The body substance, which is permeated by the canal system, High Cases
contains in the present species minute needles of silex (Fig. 3D), ate Sue
each ,!, of an inch in length, scattered rather irregularly throughout 1 and 2 a, x.
the body tissues, but sometimes forming an obscure scaffolding. In
the skin, the needles are joined into bundles, which unite at
their ends to form a network, in the meshes of which are groups of
pores. The body-tissues are composed of cells of various kinds, some
of which are concerned in nutrition, others in secreting the skeleton ;
others, again, line the surface of the canals and of the body.

At certain seasons the body develops egg-cells, which, after
fertilisation, form little oval ciliated embryos ; these swim about for
a day or two, settle down, and become sponges, the ciliated cells
becoming collar-cells. The organism, being unable to roam in
search of food, sets up currents which convey food to it.

Halichondria is a Siliceous Sponge belonging to the order Mon-
axonida, because its skeleton is composed solely of siliceous spicules
having one axis.

A very brief account of one of the simplest sponges may help
further to elucidate the structure of these organisms. The Cal-
careous Sponge, Clathrina blanca (Fig. 4) and Case 24, in its earliest
stave forms a minute thin-walled sac opening at the summit by the
oscule. The interior of the sac is lined with collar-cells, and the
wall is perforated by fine pores. Currents enter through the pores
and leave by the oscule. The thin wall is supported by three-rayed
spicules of carbonate of lime. The canal system is here in its
simplest form. In Sycon ciliatum (Table Case 24) the wall of
the sac gives off horizontally arranged tubular pockets, which alone
are lined with collar-cells. A piece of the inner wall of the large
specimen of Sycon ramsayi (2A) shows the honeycomb-like openings
of the tubes.

CLASSIFICATION,

The composition and structure of the skeleton afford the most
reliable characters for the classification of Sponges. The skeleton is
composed either of calcium carbonate, silica, or horny material
usually in the form of fibre. The calcium carbonate and silica are,
for the most part, secreted in the form of sprcuULES, which may be
Separate or fused together. A few sponges do not form a skeleton,
A simple scheme of classification is given below :—

Class I, CALCAREA, Calcareous Sponges, Skeleton calcareous

High Cases
I-VI. and
Table Cases
1 and 2 4, B.

24 GUIDE TO THE CORAL GALLERY.

Class II. SILICEA (silez, flint). Skeleton siliceous, horny, or
absent.

Fig. 4.

A. Clathrina blanca xX 20. 3B. The same x 80 (partly diagrammatic). a, oscule ;
b, pores; c, spicules; d, portion of wall turned back. o. Transverse section
of sponge (diagrammatic). vp. A three-rayed spicule x 300 diameters.
E. Collar cells x 1,200 diameters. (After E. A. Minchin.)

Sub-Class I. HExacrineLipA (hea, six; dktis,ray). Six-Ray or
Glass Sponges. Siliceous spicules typically with three axes and six rays,

PORIFERA [SPONGES]. 25

Sub-Class II. Dremosponarm (demos, multitude), including all
sponges other than Calcarea and Hexactinellida.

Grade I. TerracTINELLIpA (tetra, four; aktis, ray). Four-Ray
or Anchor Sponges. Siliceous spicules typically with four axes and
four rays ; also certain fleshy sponges (Carnosa) are included here.

Grade II. MonaxonrmpA (monos, single ; avon, axis). Monaxon
Sponges. Siliceous spicules rod- or pin-shaped.

Grade III. Kuravosa (keras, horn). Horny Sponges. Skeleton
of horny fibre.

Grade IV. Myxosroneipa (myzra, slime). Slime Sponges. With-
out a skeleton.

Crass I. CALCAREA [CaLcargous SponcEs].

The Caleareous Sponges form a comparatively small group, only
about 200 recent species being known. They live for the most part
in shallow water, and prefer shady sheltered localities.

The skeleton is composed of spicules of carbonate of lime, which
are either separate, or, in a few instances, fused into a solid frame-
work. The spicules are either three-rayed, four-rayed, needle-shaped,
or, in one instance, spherulitic.

The Asconide, which are the simplest of all sponges, are formed
of thin-walled branching tubes, lined with collar-cells throughout
their inner surface. The tubular branches may be separate (Lewco-
solenia), or may join to form a network (Clathrina).

In the Syconide the collar-cells are restricted to “radial tubes”
surrounding a central cavity devoid of collar-cells.

The beautiful Ciliated Sycon (Sycon ciliatum) is one of the
commonest sponges round our coasts, where it is found attached to
rocks and seaweeds. This sponge, which is usually about an inch in
height, has the form of a little oval white sac with a silvery crown of
spicules round the orifice (oscule). The crown of spicules is fully
expanded when currents are passing through, but otherwise it is
closed. The wall of the sac is formed of horizontally arranged
closely-packed tubes each opening by a comparatively wide aperture
into the vertical central cavity, but ending blindly on the outer
surface of the sponge. Currents pass through microscopic orifices
in the walls of the radial tubes into the interior of those tubes and
into the central cavity, and finally leave through the oscule.

A very large specimen of a Sycon Sponge, over eight inches in
length, from Poole Harbour, is exhibited in the Case,

High Cases
I-VI. and
Table Cases
1 and 2 4, B.

Table Case 2a.

Table Case 24.

High Case
Tae

Table Case
2 A, B.

26 GUIDE TO THE CORAL GALLERY.

The Compressed Grantia (Grantia compressa), which forms com-
pressed sacs resembling little paper bags, is also common round the
British coast.

Sus-Ciass I. Hexactrnettmpa [Stx-Ray orn Guass SPoncus].

The Hexactinellida, which include many remarkable and beau-
tiful forms, nearly all come from great depths, ranging from 90 to
3,000 fathoms.

The SKELETON is built up of siliceous spicules, each typically
possessing three axes and six rays, or of spicules derived from this
type; three bars of equal length crossing each other at right angles
through a common centre would give the typical form of a regular
six-rayed spicule. Endless modifications of this form occur; the
rays may be curved or branched, or one or more of the rays may
disappear, giving rise to five-rayed, four-rayed, three-rayed, two-
rayed, or one-rayed forms (Fig. 7). The spicules may be roughly
grouped into two kinds—large “skeleton” spicules, which form the
bulk of the framework, and scattered flesh-spicules of microscopic
size.

The SOFT TISSUES are arranged as follows: in the wall of a
typical cup-shaped Hexactinellid, a layer of relatively large thimble-
shaped whip chambers is separated from an outer dermal and
an inner gastral membrane by loose reticulate tissue. Currents
always enter by the dermal membrane, pass through the convex
surfaces of the whip chambers, and leave through the gastral
membrane. The large central cavity, so often present, is termed
the gastral cavity. Hexactinellida are divided into two sub-orders.

Sub-Order I. Lyssacrna. In this group the skeleton spicules
are separate throughout life, or, in cases where they are more or less
fused in later life, were separate in early stages.

Euplectella aspergillum, or Venus’ Flower-Basket (Figs. 5, 6 ;
and specimens in Case III. 2, and Table Case 24), forms an elegant
cornucopia-shaped skeleton, now often seen as an ornament. In life
the skeleton is concealed by a gelatinous flesh. The lattice-like frame-
work of the skeleton is formed of longitudinal, transverse and oblique
strands, the last forming the prominent ridges on the surface; the
strands are built up of the fused rays of very large four-rayed and three-
rayed spicules. At the lower end is a matted tuft of spicules, by means
of which the sponge is rooted in the mud. A surface layer of separate
sword-shaped spicules, each with its handle tipped with a lovely little

Euplectella imperialis (to the left) and 2. aspergillum (Venus’ Flower-Basket).
(One-sixth natural size.)

To face p. 26.

Fig. 6.

Euplectella aspergillum. a. Section of a ridge and part of wall x 15. a, dermal
layer; b, flagellated chambers; ¢, gastral cavity; d, handles of sword-shaped
spicules each tipped with a floricome. 38. Regular six-rayed spicule x 100.
c. Floricome spicule x 300. (After F. E. Schulze.)

To face p. 26.

or a “a
ate cae
a , bed

PORIFERA [SPONGES |. 27

“ floricome ” spicule, is characteristic of Euplectellid Sponges (Fig. 6C). High Case
The peculiar circular holes in the wall of the sponge ailow of direct eens
. . . . mo adie Uase
communication between the outside and the interior. The large 9,4 3.

Gai

Spicules of Glass Sponges (magnified). In the centre a node of the Dictyonine network of a
Ventriculite Sponge.

gastral cavity is closed at the summit by asieve-plate. 4. aspergillum
is obtained from a depth of 90 fathoms off Cebu, Philippines. The
magnificent /uplectella imperialis (Fig. 5; and specimens in

High Case
IE
Table Case
2 A, B.

a
i ee
ae ee sca aia Y

iy STEN PL HS BPRS STS

Lower end of aspi-
cule of the glass
rope magnified.
a, axial canals of
five aborted rays,

28 GUIDE TO THE CORAL GALLERY.

Case III. 3) comes from Japan. Specimens of the
two species have been photographed together for
comparison.

The fine specimen of Walteria leuckarti, from

Sagami Bay, Japan (Fig. 9; and Case III. 3),
consists of a long hollow thick-walled tube rising
from a solid base, and with solid pinnate branches
arising from the tube at right angles; the oval
sharp-edged openings in the wall of the tube are
oscules. The little elevations on the surface of
the branches are caused by a commensal zoophyte.
Rhabdocalyptus victor (Fig. 10) and specimen in
Case III. 3, from the same locality as the previous
species, forms a deep thin-walled vase of felt-like
texture.
The beautiful Lace Sponge, Semperella schultzei
(specimens in Case III. 1, and Table Case 28),
has a straight or curved conico-cylindrical body
terminating below in a massive root-tuft. The
surface shows a delicate gauze-like network, the
dermal membrane (Fig. 11), and also long bands
and patches of coarser pattern ; the latter are sieve-
plates covering the oscules. In place of a simple
central cavity with one terminal oscule and sieve-
plate, as in Venus’ Flower-Basket, there is a main
central cavity giving off lateral branching tubes,
the surface-openings of which are covered with the
sieve-plates ; accordingly currents enter the fine
gauze-like areas and leave by the coarser sieve-
plate areas.

Hyalonema sieboldit, or the Glass-rope Sponge
(Figs. 8, 12) and specimen in Case III. 3, comes
from Japan, closely allied species, however, being
widely distributed. When the glass ropes (without
the upper portion of the sponge) first arrived in
Europe, they were supposed to be either artificial
productions or the axial core of Gorgonid Corals.
The twisted strand or glass rope is a root-tuft
composed of immensely long spicules, which root
the sponge in the mud, and which, at the upper
end, project like a spike into the interior of the
sponge-body. Some of the long spicules end in a
toothed disk, and are provided along their length

Eig: 9:

Walteria leuckarti.

An Kuplectellid Sponge.

(One-sixth natural size.)

lo face p. *

te

Fic. 10.

Rhabdocalyptus victor. A Lyssacine Sponge. (One-fifth natural size.)

To face p. 28.

Wie, TU.

Surface network of Semperella,schultzei, the Lace Sponge.
(Natural size.)

To face p. 28.

i bed -
: |
»» a
| =
2
ioe,
ha
\
: ‘
ver, &
=
'
fn
: ‘
1)
~ i
7:
a
i
. ° e
sl
- \ ; 4
wed :
f
j
‘
od ‘
‘ i 9 ih as
re P Le d “‘* > iy
me a) Ses ee eee ee ESS teary hor ©
; ie
£050) oie iea ie
Wig - 4 y an ,
=
a é
: , a
- ; a
- 7 > —
i : :
y 4 7 py 2 ae

Fic, 12.

Hyalonema sieboldii, the Glass-Rope Sponge. (One-fourth natural size.)

To face p,.28.

PORIFERA | SPONGES ]. 29

with a serrated spiral ridge with the teeth pointing upwards as
(Fig. 8). Table Case

The body of the sponge forms a thick-walled cup, which, how- 24, 8.
ever, isso loosely constructed that light can be seen throughit. The
interior is divided up by four to eight vertical partitions radiating
from a central spike. The top of the cup is closed by a thin sieve-
plate with perforated ‘“ quarters’ corresponding to the divisions
inside. A “commensal” zoophyte (Palythoa) is always found
investing the upper end of the glass rope, and occasionally forms
pits (often mistaken for escules) on the surface of the sponge itself.
Unfortunately the Palythoa has become detached from the upper
part of the root-tuft of the specimen figured, but is abundant on the
surface of the sponge body. The Japanese deep-sea shark-fishers
obtain the sponge by means of hooks attached to their deep-sea lines.
By a curious parallel, the deep-sea shark-fishers of Portugal obtain a
nearly allied species of Hyalonema in somewhat the same manner.

Lophocalyx philippinensis, from Cebu (in fluid, Table Case 24),
which forms a small compact thick-walled cup with long root-tufts,
furnishes a beautiful example of bud formation, buds of all ages
being present on the specimens.

Sub-Order II. Dicryonina. In this group the alleleaene even in
the earliest stages, forms a rigid framework constructed of the fused
rays of large regular six-rayed spicules. These sponges usually have
a vitreous, finely honeycombed appearance. The magnificent
Aphrocallistes vastus (Fig. 1), in the centre of Case ITI., is shaped
like a vase with a thick stem, and with large folds projecting out
from the walls. The very fine specimen of Chonelasma calyx, to the
right of the former, is bowl-shaped, and with finger-like pockets
often extending down, like the “roots” of a Banyan tree, till they
reach the base on which the sponge is growing. The fossil Ventri-
culites common in flints from the Chalk are Dictyonine Sponges.

CLASS III.—DEMOSPONGLH OR COMMON SPONGES.

The Common Sponges include all sponges other than the
Calcareous and Glass Sponges.

TETRACTINELLIDA (FouR-Ray SPONGES).

The sponges of this Order are often spherical with a radiating ae IV.
structure (Cruniella, [V. 3), or they may form tough leathery cakes Partition.

30 GUIDE TO THE CORAL GALLERY.

High CaseIV. with a conspicuous rind (Cydonium japonicum, IV. 4), or rigid
plates or masses of stony hardness (Corallistes bowerbanki, IV. 4).
The Order is divided into two groups, the Choristida with separate

Right
Partition.

Fie. 13.

i \

meals ates

real i X

Trident spicules of Tetractinellid Sponges.
(Magnified 200 diameters.)

spicules, and the Lithistida
with peculiar “desma” spi-
cules, which are usually articu-
lated to form a rigid stony
skeleton. Some species possess
“ caltrop ” spicules, with four
axes and four rays. The most
characteristic spicule, however,
is the trident, with a long
shaft and three prongs, which
may project forwards or be
bent backwards or outwards
(Fig. 13). The tridents are
arranged with the shafts point-
ing inwards and the prongs
spreading tangentially beneath
the surface or projecting out-
wards. ‘Tridents and needles
in varying proportions often
form thick radiating bundles.
The Geodine Sponges (Geo-
dia, Cydonium) possess a thick
outer crust or rind, composed
of solid globular spicules
(Fig. 14). The “desmas” of
Lithistid Sponges are formed
by the deposition of concentric
layers of silica round a minute
rod or caltrop ; on this nucleus
there arise nodulated branches,
which articulate with the
branches of other desmas to
form a rigid framework. In
addition to the “skeleton”
spicules, there occur in this
Order very minute S-shaped,
spiral, and stellate flesh-spi-

cules, which are of great aid in determining the affinities of the

various species.

PORTFERA [SPONGES]. 31

CARNOSA OR FLESHY SPONGES.

The sponges of this small group either have no hard skeleton at Case IV. 3.
all (Chondrosia), or merely scattered stellate spicules (Chondrilla).
They possess a well-marked rind inclosing a softer “ pith,” and the
canal system is highly developed.

Chondrosia reniformis, or the Sea-Kidney (Case IV. 3), has a

Fic. 14.

Section of Geodia showing crust of globular spicules, radiating bundles of
tridents and needles, and small star-shaped flesh spicules. Magnified 50
diameters. (After Bowerbank.)

smooth rounded surface, on which one or two small circular oscules
are present ; the numerous pores are not visible to the naked eye.
The sponge, being devoid of a hard skeleton, shrinks greatly when
dried, but swells up again on being immersed in fluid. Apart from
the absence of trident spicules and of a hard skeleton, the Carnosa
show many affinities with the Four-Ray Sponges.

High Cases
Iy.-VI.

32 GUIDE TO THE CORAL GALLERY.

MonaxonIpA (Monaxon SPONGES).

This Order contains by far the largest number of species. The
skeleton-spicules are uniaxial, ¢.¢., shaped like rods, like needles
pointed at one or both ends, or like pins; six-rayed and four-rayed
spicules never occur. The spicules may be scattered or united into
bundles, and may form radiating or reticulate scaffoldings. Flesh-
spicules may or may not be present, one of the most common forms
being buckle-shaped (Fig. 17). The huge Neptune’s Cup Sponges,
Poterion patera (on pedestals), from the East Indies, are among the
largest of Sponge forms; the skeleton is composed of a dense net-
work of bundles of pin-shaped spicules.

The large specimen of Poterion placed above the Hexactinellid
Case, and formed of three trays one above the other, belongs to a
closely allied species.

The Borne Sponces, which also have pin-shaped skeleton
spicules, are remarkable for their habit of boring into shells and
limestone.

Cliona celata (Case IV. 3) is very common in oyster shells, in
which it excavates extensive lobed galleries ; the oscules and groups
of pores are situated on conical elevations which project through
small holes in the surface of the shell. Vigorous specimens burst
through the shell and form large cork-like masses (Case IV. 3),
the identity of which with the boring portion was for a long time
unsuspected. The magnificent specimen of Caulospongia verticillata
(Fig. 15; Case IV. 2) has a thick main stem branching into three,
the stems giving rise to closely-set whorls (or spirals) of thin lamellae
gradually diminishing in size from below upwards.

The massive Suberites wilsont (Case TV. 8) is remarkable for its
brilliant purple colour. The colouring matter forms a rich purple
solution in acidified alcohol. speriopsis challengeri (Fig. 16), from
825 fathoms, east of Celebes (specimen in fluid, Case IV. 4), one of
the “Challenger” treasures, has a main stem giving off along one
edge a series of stalked bowl-shaped fronds increasing in size from
below upwards. The in-current pores are situated in the concavity,
and the minute oscules on the convex surface of each bowl.

The series of specimens of Echinonema typicum (Case IV. 4)
shows well the great variation in form that may occur in one and
the same species.

FRESH-WATER Sponges (Case VI. 3, facing west) are common

Hie. 15.

Caulos qia vertici id §
pongia verticillata. A Monaxonid Sponge. (One-seventh natural size.)

To face p. 32.

ee ec Fell Si aaah OF eae por ‘Soi. : i aos

:
rn

Fic. 16.

Esperiopsis challengeri. A Monaxonid Sponge. (Two-thirds natural size.)
The figure on the left shows oscular, and that on the right, poral surfaces of
the sponge leaflets.

To face p. 32

Fig. 17.

SET

FR

atts,
By) ~

Siliceous spicules of Monaxonid Sponges. (Magnified 200-300 diameters.)
D

High Cases
IV.-VI.

High Cases
I. II. and
Table Case 1.

o4 GUIDE TO THE CORAL GALLERY.

in lakes and rivers attached to stems of reeds or the piles of locks, &e.
These sponges are often of a bright green colour, and are easily
mistaken for waterweeds. The green colour, which is due to the
presence of chlorophyll, does not occur in specimens living in shady
places, the sponges then being pale buff. Alcohol dissolves out the
colour, forming a clear green solution.

Spongilla lacustris forms green crusts from which long digitate
branches arise.

The black Parmula batesii (Case VI. 3), from the Amazons, is
often found attached to branches of trees submerged during the rainy
season, the sponges being left high and dry when the floods subside.

Many fresh-water sponges produce little seed-like buds or
gemmules, which possess a hard resistant capsule perforated by a
pore at one point. When the favourable season arrives, the contents
of the gemmule burst through the pore and develop into a sponge.

In the Chalinid Sponges (Cases V., VI.), the skeleton forms a
network of horny fibres cored by siliceous spicules ; if the latter
were absent from the fibres, the sponges would be Horny Sponges,
and it is generally supposed that the pure horny sponges have been
derived from siliceous forms which no longer secrete silex.

Keratosa (Horny Sponcss).

The Horny Sponges possess a skeleton of horny fibres, which
generally form a close network, as in the Bath Sponges, or the fibres
may branch in a tree-like manner. Very commonly, foreign bodies,
such as sand grains, the spicules of other sponges, &c., are present in
the body of the sponge or in the axis of the fibres; even in the
finest bath sponges there are scattered sand grains in the main
fibres.

A series of commercial sponges is set out in Case I. and Table
Case I.

The Fine Turkey Sponge, Spongia officinalis (Fig. 18), has a cup-
shaped body with a black or dark skin. The oscules are situated on
the floor of the cup. A section of the body shows a comparatively
uniform pale yellow surface, the canals being slightly darker in tint.
Groups of pores on the outer surface lead by short fine canals into
spaces just below the skin ; from the floor of these spaces canals pass
inwards, branching and gradually diminishing in size, till they reach
groups of pear-shaped whip chambers, with the cavities of which they
communicate through minute orifices in the walls of the latter.

ad

PORIFERA [SPONGES ]. 39

Groups of whip chambers lead each by a short passage into a common ee es
channel, which joins with other canaliculi to form canals, finally Table Case 1.
opening by the oscules. The whip chambers form a sort of
cordon between the extreme rootlets of the in-current and out-
current canals.

The horny skeleton, which is imbedded in and which supports
the tissues of the body, forms a network composed of radiating
main fibres connected by a dense meshwork of finer secondary
fibres.

The Common Bath Sponge, Hippospongia equina, has a massive
cake-shaped body covered with black or dark skin. The body is
permeated by wide channels and cavities separated from each other by

«
oscule ¥
o~

Toilet Sponge. a. Diagram of Canal System. 8. Section showing a, pores ;
b, canals; ¢, whip-chambers; d, skeleton fibres ; d’, main fibre; e, embryo.
c. Whip-chambers. Highly magnified. (After F. E. Schulze.)

thin walls. The Common Bath Sponge is, in fact, composed of
contorted lamellae separated by labyrinthine Spaces (Fig. 19) ; the
large holes on the surface are not oscules, but ‘“ pseudoscules,” the
true oscules and groups of pores being scattered indiscriminately over
the surface of the lamellae or walls of the Spaces. Currents always
come out of a true oscule, but they may enter or leave by the holes
on the surface of the Common Bath Sponge. See specimens in fluid
in Case I.

On the floor of Case I. is a broken pitcher with the skeletons of
a bath sponge and fine toilet sponge growing on it.

The Spongia zimocca, or Hard Sponge, which forms a third species

D 2

High Cases
I. IT. and
Table Case 1.

36 GUIDE TO THE CORAL GALLERY.

of commercial sponge, has a flat disk-shaped body with numerous
oscules on the upper surface.

The Levant Lappet, which is a variety of Spongia officinalis,
forms huge thin flaps like an elephant’s ear ; occasionally the edges
of the flap unite to form a capacious funnel-shaped cup.

The above three species (S. officinalis, S. zimocca, and H. equina)
include numerous varieties and variations which need not be further
alluded to here.

Commercial Sponges flourish in sub-tropical and tropical waters in
depths of 2 to 100 fathoms, the world’s supply coming almost entirely

Fic. 19.

Section of Hippospongia equina, the Common Bath Sponge. (Natural size.)

from the West Indies and eastern half of the Mediterranean. In the
latter region they are collected by-divers, who descend naked or in
diving-dresses, or by men who hook up specimens by means of a
long harpoon ; dredges are employed in deeper waters. In the West
Indies (Florida, Bahamas, &c.) the hooking method is employed, a
bucket with a pane of glass in the bottom being used as a submarine
spy-glass to do away with the effect of the surface ripples.

Sponges are prepared for market by macerating them in sea-
water in staked enclosures ; after a few days the skin and flesh rot
off, and can then be beaten out; the skeletons are hung up in
strings to dry and bleach in the air and sun.

PORIFERA |SPONGES |. 37

Sponges are sometimes cultivated from cuttings, care being taken High Cases
that a portion of the skin is retained in each piece. It takes about 1. 1. and
ae p Table Case 1.
seven years for a cubic inch of sponge to grow to a marketable size.
Attention is directed to the gigantic Luffaria archeri, Neptune’s
Trumpet (Case IT.), from Yucatan, and to the fine fan-shaped
specimen of Janthella flabelliformis beneath it (Case II.) ; the skeleton
fibres in these sponges are comparatively thick and cored with a
thick pith, those of the bath sponges being solid, or with only a
slender core of pith. The specimen of Phyllospongia foliascens
(Case II. 4) shows a curious likeness to a Turbinarian coral, the
oscules of the sponge resembling the calicles of the coral; but it
is uncertain whether these resemblances have any real significance.
Myxosponeipa or SLIME SPONGES comprise a small group
characterised by the entire absence of a skeleton. Halisarca forms
yellowish-brown slimy crusts on stones.
[A series of specimens and diagrams illustrating the structure of
Sponges is exhibited in an upright table case at the eastern end of
the Coral Gallery. ]

38 GUIDE TO THE CORAL GALLERY.

HYDROZOA.

[(*) An asterisk against names of species denotes that specimens in fluid
are exhibited in the upright part of Table Case 3.]

INTRODUCTION.

The exhibited collection of Hydrozoa occupies Cases 2-4 at the
eastern end of the Coral Gallery.

The members of the class occur as fixed plant-like forms often of
horny texture (Sertularia, &c., Case 3), or as massive or branched
coral-like growths (Stylaster and Millepora, Cases 2, 4), or as
transparent free-swimming bell- or disk-shaped organisms, which
may be simple (Meduse or Jelly-Fish, Case 3), or may form colonies
composed of variously modified individuals (Siphonophora, Case 3).
The vast majority of species are marine, but a few live in fresh
water.

The specimens in Case 3 A, B, closely resemble dried seaweeds, but
can generally be distinguished from plants by observing, especially
with a lens, that a serrated appearance of the branches is due to
little horny cups or receptacles ; see, for instance, Diphasia tamarisca,*
which has unusually large cylindrical cups. In life, each cup
contains a polyp with a crown of tentacles surrounding a mouth
opening into a stomach cavity.

In spite of great differences in form amongst the Hydrozoa, a
comparatively simple plan of organisation can be traced in all.

To briefly explain this, an account is given of Hydra or the
Fresh-Water Polyp, a tiny Hydrozoon which lives in ponds attached
to water-weeds (Fig. 14). Hydra, which is green or reddish-brown
in colour, according to the species, attains an average height of
about one-third of an inch. The little creature alters its shape
considerably, being now contracted down to a lump, now expanded
into a little column with a circle of thread-like tentacles near the
summit. When a tentacle touches some small organism, the latter
is paralysed and drawn into the mouth at the top of the column,
and thence into the simple stomach-cavity, where it is digested, the
remains being evacuated by the mouth. Between the mouth and

HYDROZOA. 39

the circle of tentacles is an area termed the hypostome (Fig. 18, hyp.).
The animal is a simple sac, the wall of which is formed of two layers
of cells, an outer or ectoderm layer, one or more cells deep, and an
inner or endoderm layer, one cell deep (Fig. 18, ect. end.), the layers
being separated by a thin structureless lamella (Fig. 1, ms. gl.).

pee)

Nene ir
te

on
2 Fa
3 el Coe
CR J BS
Ro Cf
& UG
QO ent.
BR cay Te
Fy cr
es 7
iy
DIMES
(7
AMUN:
A CPLA c
B

a. Hydra on pond weed, slightly enlarged. (From nature.) 3B. Section of
Hydra, highly magnified. mth, mouth; hyp, hypostome ; ent. cav., stomach ;
end, endoderm; ect, ectoderm; msgl, structureless lamella; bd 1, 2, buds;
ovy, ovary ; spy, spermary ; ntc, thread cell. (After Parker and Haswell.)
o. Thread cell, very highly magnified. (After F. E. Schulze.)

The endoderm, which lines the whole inner cavity and the interior
of the tentacles, is concerned in the digestion of food. In the
ectoderm are certain peculiar cells, each containing a cyst with a
barbed thread coiled up inside (Fig. 1c); a pointed process pro-
jecting from the outer surface of the cell acts as a trigger, which,

Case 3.

40 GUIDE TO THE CORAL GALLERY.

on being touched, causes the barbed thread to be everted, thereby
stinging and poisoning the prey. Thread-cells are characteristic of
the Coelentera. Hydra reproduces itself sexually by means of eggs,
which form in little wart-like swellings on the surface ; or asexually,
by forming buds which grow out from the wall, develop mouth and
tentacles, and normally become detached. Hydra, which is named
after the monster of the fable, can be cut into pieces, and, condition-
ally on containing a portion of the two cell layers, each fragment
will develop into a complete animal.

CLASSIFICATION.

Having given a brief outline of the structure of one of the
simplest forms, an account will now be given of the groups of
Hydrozoa, which, for convenience of description, will be referred to
under the three headings :—

I. Hydroida (Hydroid Zoophytes).

II. Hydrocorallinze (Coral-like Hydrozoa).

III. Medusze and other allied free-swimming forms (Jelly-Fish,
Siphonophora, and Ctenophora or Comb-Jellies).

I. HYDROIDA (HYDROID ZOOPHYTES).

The horny plant-like growths in Case 3 A, B, have fundamentally
the same structure as the Hydra. If the little sac were to form a
horny protective cover on its surface, to become longer, to give off
buds, which likewise budded, all the buds remaining in connection
with each other, and each surmounted by its crown of tentacles—a
plant-like Hydroid colony would be the result. Bougainvillea
fruticosa* (Figs. 2, 3, and specimen in Case 3) isa branching Hydroid
colony, every branch terminating in a polyp, as each individual of a
colony is termed. All the polyps are vitally connected with each other
by the common living tissues inside the stems. The polyps are of two
kinds, one kind being in the form of an elongated sac or tube with a
crown of tentacles, that is to say, like Hydra; while the other, when
mature, resembles a small Medusa or Jelly-Fish. The Medusa-like
polyp (Fig. 4) ultimately becomes detached and swims away. The
little free-swimming polyp, which we must now call a Medusa, is bell-
shaped ; the true mouth, which leads into the stomach, is at the end
of the clapper (manubrium) hanging down from the centre of the

HYDROZOA. 41

concavity of the bell or “‘umbrella’’; four radial canals pass from Case 3.
the central stomach to open into a circular canal round the margin

of the umbrella ; from the same margin are suspended four pairs of
tentacles, each tentacle being provided at its base with an eye-spot.

The opening of the umbrella is partly closed by a narrow circular

band, the veil or velum, extending in from the rim; and, most
important of all, the eggs are situated in the walls of the manubrium.

The organism swims by alternate contraction and relaxation of the
umbrella.

The little Medusa is simply an extremely modified polyp, specially

igh oy

Colony of Bougainvillea fruticosa, natural size, attached to the underside of a
piece of floating timber (After Allman.)

adapted for a free-swimming existence. If a Hydra were shortened
and drawn out laterally (Fig. 5), a shape somewhat like that of a
Medusa would result. The Medusa has nervous and muscular
apparatus and sense organs in correspondence with its active
existence, these being absent in the fixed polyps.

A colony of Bougainvillea, then, is made up of individuals of two
kinds, feeding or nutritive polyps, whose function it is to obtain and
digest food for the colony, and generative polyps, whose function it
is to form and carry the eggs. Here we have division of labour, and

1 From ‘‘ Encyclopedia Britannica.”

Case 3.

42 GUIDE TO THE CORAL GALLERY.

corresponding alteration of form (dimorphism) among the units of
the colony.

The fertilised egg of the Medusa develops into the fixed Hydroid
colony, the latter forming buds in which the eggs are produced.
This is an instance of alternation of generations, a phenomenon very
common among the Hydrozoa, but especially marked in cases where
the asexually formed generative polyp or individual becomes detached
and swims away.

Portion of a colony of Bougainvillea fruticosa, magnified. (After
Allman).

In cases where the generative polyps are free-swimming, advan-
tage would result from the eggs being scattered over a wide area, and
not crowded in the neighbourhood of the parent stock ; and, further
the egg-carrying polyp (Medusa) can swim to the surface where food
is plentiful. The free generative polyp, or Medusa of Clavatella
prolifera (Fig. 6), shows a transition between a feeding polyp and
Medusa. The umbrella can scarcely be said to exist in this case, the

' From ‘‘ Hineyclopedia Britannica.”

HYDROZOA. 43

Medusa being unable to swim, but only capable of creeping about on Case 3.
its peculiar tentacles.

Free-swimming generative polyps or Medusz occur only in some
Hydroids ; in many species the generative polyps remain on the
colony and produce the eggs in this situation; in such cases they
lose, to a greater or less extent, their Medusan structure and may be
reduced to a mere wart (Fig. 7).

Generative polyps may arise from the stem as in Lougainvillea,
but very commonly they arise from tne sides of a degenerate feeding
polyp which has lost its mouth and tentacles, and is then termed a
blastostyle ; the latter, with its buds, may be naked (Hydractinia,

Fig. 9), or invested with a horny capsule (Sertwlaria, Fig. 12 Bb).

The Hydroida are divided into two
groups——Athecata and Thecaphora.

ATHECATA (or Gymnoblastea-Antho-
meduse). In this group the feeding
polyps cannot be withdrawn into horny
cups, and the generative polyps or
buds are not enclosed in horny capsules.
The Medusz (Anthomeduse) form the
eges in the walls of the manubrium.
Tubularia indivisa,* or the “Tubular
Coralline like Oaten Pipes” of Ellis, forms
clusters of simple stems from six to
twelve inches in height, rising from a
twisted mass of roots. Each stem, in
life, is crowned with a red flower-like
polyp with two sets of filiform tentacles,
one set being near the mouth and the free cenerative polyp or
other at the base; festoons of stalked Medusa of Bougainvil-

. lea fruticosa. a, manu-
generative polyps or buds hang down jyium: 8, radial canals;
from the base of the feeding polyp. c, vellum ; d, naked eye-
Each bud contains a degenerate Medusa, “P's: (After Allman.)
which never escapes to lead a free life, but produces the eggs in its
attached situation. The fertilised egg develops into a peculiar embryo,
which becomes fixed and grows up into a long-stemmed polyp.

Tubularia larynz* has branched annulated stems. The apparent
branches on 7. indivisa arise from embryos settling on the older
stems.

The fine specimen of Pennaria cavolinii* from Naples shows a
branching colony, the polyps of which possess a ring of filiform

Case 3.

44 GUIDE TO THE CORAL GALLERY.

tentacles at the base and scattered knobbed tentacles above. The
two kinds of tentacles can be clearly seen in this specimen with the
aid of a simple lens.

Hydractinia echinata* (Figs. 8, 9) is always found forming a white
fleecy covering on univalve shells inhabited by Hermit Crabs. “The
waving forest of tall and graceful polypites generally reaches its
greatest height towards the mouth (of the shell), round the edge of
which are set the curious snake-
like appendages. Intermingling
with the perfect polypites are the
rudimentary zooids, which carry
the generative sacs, attenuated by
/ their work and looking as if
weighed down by their burden”
(Hincks). The polyps rise from a
chitinous crust covered with conical
serrated spines.

Monocaulus imperator* (Fig.
10), one of the most remarkable
acquisitions of the Challenger Expe-
dition, was obtained from depths
of 1,875 and 2,900 fathoms in
the North Pacific. A naked stem
over seven feet in length, and
bulbous at the lower end, is sur-
mounted by a large polyp with
basal and oral circles of filiform

URAL ae tentacles. The polyp was pale
A. Diagram of a Hydroid feeding polyp _. si cake 5

(longitudinal section); B, of a Hy- Pink, and measured nine inches in
droid Medusa. 0, mouth; g, gastric breadth across the expanded basal
noate 4 ae eee ee circle of tentacles. The exhibited
and endoderm; rk, radial canal; specimen (Case 3) is sadly altered
v, velum ; rék, circular canal. (From from what it was in life: but. as
Lang’s Text-book Comp. Anat.) : : , 2
Sir Wyville Thompson observed,
‘these delicate things, drawn up rapidly through the water from a
depth of four statute miles, suffer greatly from this violent change.”

The specimens almost seemed to melt away, and had to be
promptly put into alcohol, which has hardened and contracted them
to their present condition.

Cordylophora lacustris* is a fresh-water Hydroid, with branches
rising from a creeping stolon to a height of two or three inches ;

Wa. 5.

HYDROZOA. 45

the polyps are ovoid and provided with scattered filiform Case 3.
tentacles.

The dried specimens of Ceratella and Chitina in Case 3A are
composed of a dense network of horny tubes. In life the surface of
the branches is covered with large club-shaped polyps provided with
scattered knobbed tentacles.

THECAPHORA (or Calyptoblastea-Leptomeduse). This group in-
cludes many of the more familiar forms of zoophytes (Case 3 A, B).

Fic. 6.

A. Clavatella prolifera (magnified) ; at base, clusters of generative polyps, one ot
which is nearly ready to become detached. B. Free creeping generative polyp
or Medusa, highly magnified ; b, the same slightly enlarged. (After Hincks.)

The feeding polyps can be retracted into horny cups, and the
generative polyps (which are budded off from a blastostyle, and
which may be fixed or free-swimming) are enclosed in a horny
capsule. The Medusze (Leptomeduse) develop the eggs in the
radial canals. There are three sub-groups—the Campanularina,
with stalked cups, the Sertularina, with sessile cups, and the Plumu-
larina, in which occur little supplementary cups called nematophores,
containing an offshoot from the common body substance of the
colony loaded with thread-cells.

Case 3.

Case 3A.

Case 3A.

Case 3B.

46 GUIDE TO THE CORAL GALLERY.

Obelia longissima* (Obelia sp., Fig. 11) forms very slender
branching - stems; the cups are borne on ringed pedicels, and
resemble wineglasses. The generative polyps, which are borne on a
blastostyle, become free Meduse.* The latter are tiny crystal bells
with numerous tentacles and with eight litho-cysts ; they often swim
with the umbrella everted and the ea Eta projecting from the
centre of the convexity.

Sertularia abietina, the Sea Fir Zoophyte (Fig. 12, and specimen
in igs 3A), forms clusters of brown pinnately-branched stems from six
to twelve inches in height. It is often seen among heaps of seaweed
on the shore, or attached to oyster and scallop shells in fishmongers’
shops ; the rather large horny cups, which are arranged alternately on

Diagrams illustrating the gradual degeneration of the Medusa bud into
a mere rounded swelling. The black represents the stomach and its
continuations; the lighter shading represents the reproductive cells.
A. Attached Medusa; B. The same with margin of umbrella closed
over manubrium; ©, D, £, further stages. (After Lankester, Encyc.
Britannica.)

each side of the branches, are swollen at the base and narrowed at the
circular orifice. The oval reproductive capsules are slightly stalked.

Sertularia argentea,* or the Squirrel’s Tail Zoophyte, S. cupressina,
the Sea Cypress, and Z’wiaria thuja, the Bottle Brush Coralline, are
all expressively named by Ellis from their general appearance. In
these species the sessile cups are arranged alternately on opposite
sides of the branches. In Hydrallmania falcata, the Sickle Coralline,
the cups are on one side only. In the five species above referred
to the generative polyps (or degenerate Medusze) are permanently
attached to a degenerate feeding polyp or blastostyle, the whole
being enclosed in a horny capsule.

Antennularia antennina, the “ Lobster’s Horn Coralline, or Sea
Beard’ * (Fig. 13, and specimen in Case 3B), forms long jointed

HYDROZOA. 47

stems giving off whorls of slender branchlets bearing the minute cups Case 3s.
and still more minute funnel-shaped nematophores.

A. ramosa (Case 3B) has branched stems.

In Aglaophenia pluma, the “ Podded Coralline,” the reproductive
capsules are protected by a pod-shaped receptacle formed by modified
branchlets which curve round and meet.

Aglaophenia urens,* from Java, is named on account of its severe
stinging properties. Some species of this genus living in the tropics
attain a height of several feet, and_it is dangerous to come in contact
with them.

Fie. 8.

Hydractinia echinata on a shell of a whelk inhabited by a Hermit Crab.
(Natural size.)

II. HYDROCORALLIN® OR CORAL-LIKE HYDROZOA.

The Hydrozoa of this group resemble the Reef Corals in forming Cases 2, 4.
a calcareous skeleton; indeed, the Hydrocoralline were supposed
to belong to the same class (Anthozoa) as the Corals, till Agassiz
showed that Millepora was a true Hydrozoon. Later, Moseley, in his
classical work on the Challenger Hydrocorallinz, confirmed Agassiz’
results, and proved that the Stylasteride were also Hydrozoa. In
all the Hydrocorallines two forms of polpys (Fig. 16) occur, viz.,
gastrozooids, with mouth and stomach, and tentacle-like dactylo-
zooids without a mouth; the gastrozooids are contained in pits

Fic. 9.

Hydractinia echinata. a, feeding polyps; b, reproductive polyps
(female). (Magnitied.)

HYDROZOA. 49

termed gastropores, and the dactylozooids in smaller pits termed dacty- Cases 2, 4.

lopores, the pores being usually arranged in systems (Figs. 15 and 18.)
Minueporipa. Millepora forms massive laminate or branched Case 4.

growths, and presents a great variety of forms ; but, according to Prof.

Hickson, there are no definite specific characters separating one form

from another, and consequently we must regard the forty or more

so-called species as mere variations of only one species, viz., Millepora

Monocaulus imperator, wpper third. (Much reduced.)

alcicornis, or the Stag’s Horn Millepora. He would call, for instance,
M. verrucosa (Case 4, upright portion) I. alcicornis, facies verrucosa.

It seems that an embryo settling down on a broad surface with
room to spread forms a laminate growth, such as the typical JM.
alcicornis or M. complanata (Case 4); but if it settles on a small
object it tends to forma branching growth. J/illepora often encrusts
old bottles, &c. ; in Case 34 a delicate network of Fan Coral is exhibited
coated with a thin crust of Millepora alcicornis. Systems consisting
of small gastropores, surrounded by irregular circles of about six still

E

A. Obelia. Bop. Meduse of same (ce, everted). bls,
blastostyle ; coe, common body tissues ; ect, end, ecto
and endoderm; ent, stomach ; gth, generative cap-
sules; hth, horny cups; 1, lithocyst; mbd, Medusa
bud; mnb, manubrium; p, horny outer covering ;
P 1,2,3, feeding polyps; rad. c., radial canal; ¢,
tentacle; v, velum. (After Parker and Haswell )

Sertularia abietina. a. Slightly enlarged. B. Branchlet magnified ; Cty polyps ;
b, reproductive capsule (original). The orifices on right side of Fig. B are
closed by horny lids. 2

EZ

52

GUIDE TO THE CORAL GALLERY.

smaller dactylopores, can be seen scattered over the surface of these

corals.

Case 4.

A section shows in the cavities of the calicles series of

Fic. 13.

LAY

SS

‘ Hg WEG

RNR

B. Joint of stem with branchlets magni-

fied; a, polyp; b, nematophore ; c, reproductive capsule.

magnified (lettering as before); after Allman.

“Up
CESS

Antennularia antennina.

c. Branchlet highly

A. Natural size.

parallel floors (tabulae) marking successive stages of growth activity,

Millepora is richly provided with thread-cells, which retain their

aS

et Eat nti

‘1

4
ee
.

14,

Fic.

(One-half natural size, )

Stylaster flabelliformis

To face p. 53.

HYDROZOA. 53

efficiency even on old dried specimens. The degenerate dactylozooids
have a number of capitate tentacles, while the gastrozooids have only
a whorl of four (Fig. 16).

In 1891 Prof. Hickson discovered the male, and in 1898 the
female Medusa (Fig. 17) of Millepora in small capsules, which, when
occurring near the surface, form rounded swellings (ampullae).
Latterly, Mr. Duerden has seen the living Medusae in his aquarium
at Jamaica. This tiny Medusa is only about ;'; inch in diameter ;
its cavity is nearly filled up by the large manubrium containing the
eggs. The umbrella is devoid of canals, tentacles, and sense-organs,
but is provided with batteries of thread- Fie. 152
cells; and usually no mouth can be
seen at the end of the manubrium.
The little creature, however, is able to
swim away with its heavy burden of
eggs from the parent colony; having
deposited the eggs, it shrivels up.

SrynasteRID&. In this family the
dactylozooids are without tentacles, and
one or both kinds of zooids are supported
in their calicles by a calcareous style.
There are several genera in this family.
: i a oe eee ae eteed Fragment of Millepora, show-
in “ cyclo-systems”’—a circle of dacty- ing the circles of dactylopores
lopores surrounding a central gastropore. _ each with a central gastropore.
A cyclo-system presents a deceptive Hee eo) oh
resemblance to the calicle of an ordinary
coral; in the latter the calicle contains one coral polyp, but in the
cyclo-system there are a dozen or more degenerate individuals sur-
rounding a central individual; the dactylozooids were formerly
supposed to be the tentacles of the central zooid. The generative
buds, which are situated in the often numerous swellings or ampullae,
never become free Medusz.

The Stylasters are remarkable for the elegance and beauty of
their arborescent fan-shaped forms (Fig. 14) and their exquisite
colouring. Several specimens of Stylaster roseus from off a cable
from the West Indies show considerable variation in colour, being
white, rose-pink, and salmon-coloured. The cyclo-systems regularly
alternate on the sides of the slender branches.

1 From ‘ Encyclopedia Britannica,”

Case 4,

\\ Case 4.

54 GUIDE TO THE CORAL GALLERY.

Case 2 ¢, D. Stylaster sanguineus, or the “ Blood Coral” from the Pacific
Islands, is of a brilliant red colour.

In Astylus (Fig. 18) the cyclo-systems all face one way. Crypto-
helia pudica is remarkable for the little canopy which arches over
each cyclo-system.

Lnistichopora has the pores arranged in a triple row along each
edge of the flattened branches, a central row of gastropores being
enclosed between two parallel rows of dactylopores. Probably the
various supposed species of Distichopora (D. coccinea, violacea, livida)
are colour variations of one species.

Fic. 16.)

Enlarged view of the surface of a living Millepora, showing five dactylopore
polyps surrounding a central gastropore polyp. (After Moseley.)

III. MEDUSA AND OTHER ALLIED FREE-SWIMMING
CCELENTERA.

Case 3, Glass models of Medusze or Sea-Nettles are exhibited in
Upright part. tn, upright part of Case 3 along with specimens in spirit. Medusz
have already been referred to in the account of Hydroida and

of Millepora, where it was stated that in some species certain

polyps carrying the eggs (generative polyps) became detached

1 From ‘‘ Encyclopedia Britannica.”

HYDROZOA. 55

from the parent colony and swam away. Im the case of many Case 3,
Medusx, the eggs develop directly into Medusa, no fixed stage Upright part.
being known; here the fixed stage, which there is reason to believe
has at one time existed in every case, has been “hurried through”
in the egg. Medusx present two very different types of structure :
in one, which may be called the “ Hydromedusan” type, the
umbrella is provided with a velum, the sense-organs are naked on
the umbrella margin (Naked-Eyed Meduse), and the fixed stock,
when known, is of the Hydra or Hydroid type, and produces buds
laterally. Meduse of this type come under the sub-class Hydro-
meduse, which includes Hydroida and Hydrocoralline.

In Medusze of the second or “Scyphomedusan” type the

Fic. 17.1

Female Medusa of Millepora, showing the eggs and marginal batteries
of thread cells. (After Prof. 8. J. Hickson.)
umbrella is without a velum, the marginal sense-organs are covered
by little lappets (Covered-Eyed Meduse), rows of “ gastral fila-
ments” project into the stomach cavity, and the fixed stock, only
known in a few cases, is a broad flattened polyp (Scyphistoma ?),
which produces buds by transverse fission (Fig. 194-c), and has four Case 3,
longitudinal ridges along the walls of the stomach cavity. Scypho- Uptisht part.
medusan Medusz are included in the sub-class Scyphomeduse.
HypRoMEDUSAN Mrpusm. The tiny Medus:e given off from the
fixed stocks of Hydroid Zoophytes come under two groups. Those

' From “ Proceedings of the Royal Society.”
* Skuphos, a cup; stoma, mouth,

Case 3,

Upright part,

Case 3,
Upright part,

56 GUIDE TO THE CORAL GALLERY.

detached from the flower-like stocks of Athecate Hydroids come
under the Anthomeduse ; they have naked eye-spots (Fig. 4), and
the eggs are formed in the walls of the manubrium; see Rathkea
Jasciculata,* a little Medusa which is given off from a small solitary
fixed polyp with four tentacles. The early history of Pandea
conica* and Tiara pileata,* both of which are Anthomedusa, is

unknown.

The Medusz of the Thecate Hydroids come under the Leptomeduse
(see Obelia,* Case 3,and Model of Rheymatodes thalassina) ; the eggs

Fic. 18}.

Portion of Astylus show-
ing cyclosystems each
with a central gas-
tropore and zone of
slite-like dactylopores.
(After Moseley.)

are formed in the radial canals, and the sense-
organs are either eye-spots or “ litho-cysts,”
the latter being vesicles containing a hard
concretion which transmits impressions from
the outside to delicate “auditory” cells. In
certain Hydromeduse the sense-organs arise
on modified tentacles known as tentaculo-cysts.
These forms, which come under Haeckel’s
Orders Trachomedusw and Narcomeduse, have
no known “ Hydroid history,” and in some
cases are known to develop direct from the
ege; see Carmarina hastata (Fig. 20), and
Model in Case 34. Two fresh-water Medusz
are known, both of which are Hydromedusw
Limnocodium sowerbii, from the Victoria Regia
Tank in the Royal Botanical Society’s Gardens,
has a shallow umbrella less than half an inch
in diameter and with numerous tentacles ;
the fixed phase occurs as a columnar polyp
about a quarter of an inch in height, simple
or branched once or twice; medusa buds
arise from the summit; the original habitat
was probably the Amazon region. ‘The second
species, Limnocnida tanganyice, comes from
Lake Tanganyika; the umbrella is about
an inch across, the manubrium is very

wide and shallow, and the stomach-cavity is nearly filled up by
the convex lens-like central area of the under surface of the

umbrella.

Finally the Meduse of Millepora and the swimming-bells, &c., of
the Siphonophora belong to the Hydromedusan type.
SCYPHOMEDUSAN Mupusm (Scyphomedus). These include the

Fic. 19.

Life history of Aurelia. a. “ Hydra tuba” on shell (Scyphistoma stage). B, ©.
The same undergoing transverse division (enlarged). Dp’, Ephyra stage
(natural size and enlarged). e& ©’. Young Aurelia (natural size and
enlarged). ¥F. Fully-grown Aurelia.

To face p. 56.

HYDROZOA. ay

larger and commoner kinds of Jelly-Fish or Sea-Nettles. A brief Case 3,
account is given below of Awrelia aurita* (Model and specimens Upright part.
in Case 3), whose phantom disks are so often seen in summer

time slowly swimming below the surface. In the centre of the

shallow umbrella are four purple horseshoe-shaped or circular

generative masses; in the centre of the under surface is the
manubrium prolonged into four arms; the margin of the umbrella

is provided with a fringe of very short fine tentacles, the uniformity

Fic. 20.

Carmarina hastata, one of the Truchomeduse. (After Haeckel, and from Encye.
Britannica.)

of the fringe being broken by eight notches, each containing
a tentaculo-cyst; each of the latter (Fig. 21) is covered by a__ Case 3,
pair of minute lappets, hence Meduse of this type were called UP™Sht part.
Covered-Eyed; while those of the Hydromedusan type, being
without lappets, were called Naked-EHyed.
The thickness of the wnbrella is traversed by a system of simple
and branched canals, which pass from the central stomach to a
circular canal running round the margin of the umbrella, Pro-

Case 3,
Upright part.

58 GUIDE TO THE CORAL GALLERY.

jecting from the stomach walls are four groups of gastral filaments
loaded with thread-cells. The purple reproductive masses project
from the floor of the stomach cavity ; at the base of the manubrium
outside are four pockets, which bring the water very near to these
masses. Aurelia has no velum in the adult state. The fertilised
egg develops into a hollow oval ciliated embryo, which settles down
and becomes a small polyp with mouth and stomach and sixteen
tentacles; this phase was formerly supposed to be a distinct
individual, which was named Hydra tuba, or the Trumpet Polypus.
A very fine example sent by the Plymouth Biological Station is
exhibited in Case 3 (Fig. 194), numerous specimens of tbe little

Fie. 21.

Tentaculocyst and marginal lappets of Aurelia aurita. In the left-hand figure
—ml, marginal lappets; ¢, tentaculocyst ; a, superior olfactory pit; mé, mar-
ginal tentacles of the disc, magnified about 50 diameters. In the right-
hand figure—a, superior olfactory pit; b, inferior olfactory pit; h, hood or
bridge joining the marginal lappets; #, tentaculocyst; con, auditory con-
cretion; oc, ocellus. (After Eimer, from Encyc. Britannica.)

polyp being attached to a shell; this fixed phase of Awrelia is now
called the “ Scyphistoma” stage, on account of the shallow cup-
like oral region, contrasting in this respect with the elongated narrow
conical oral region of Hydra and Hydroid polyps. In course of
time the little Scyphistoma undergoes “ transverse fission,” and
resembles a pile of saucers with crenulated rims (Fig. 198).
Presently the saucers detach themselves (specimens, Case 3) and
swim away; they are now known as Hphyra Meduse, or the
Ephyra stage (Fig. 19¢ ; specimens, Case 3); the last stage in this
wonderful transformation consists in the filling in of the spaces
between the eight bifid arms of the Ephyra and the development of

HYDROZOA. 59

a fringe of fine tentacles on those invervening portions, the ends of
the bifid arms now occupying the notches in the rim and forming
the lappets of the sense-organs ; the medusa is now recognisable as
Aurelia,

The fixed Scyphistoma stage is not common, many Scypho-
medusz developing direct from the egg. The Scyphomedusz are
divided into four Orders. The first Order includes the exceptional
Lucernarie-Haliclystus (Lucernaria) octoradiatus * (Fig. 22) is shaped
like a vase with a short stem. The upper edge is produced into
eight arms each crowned with a tuft of tentacles. The animal,
which fixes itself by its stalk, can creep along or swim. On the
margin, between the tufts of tentacles, are peculiar modified tentacles
known as anchoring bodies, which assist progression by sticking to
and grasping the surface of the sea-weeds or stones. The mouth

Fic. 22.

Haliclystus octoradiatus, a Lucernarian Medusa, on sea weed. a, mouth
and stomach ; b, tentacles; c, anchors; d, reproductive glands. (From
Johnston’s British Zoophytes; figures slightly altered. )
and stomach (manubrium) are in the centre. Haliclystus, which is
commonly found adhering to sea-weeds, varies in colour, being olive-
brown, green, or pink. The second Order (Discomedusae) includes
the commoner kinds of Jelly-Fish, Pelagia, Aurelia, Pilema, Coty-
lorhiza, &c. (see Case 3). In Pilema (Fig. 23) and other “ Rhizo-
stomatous”’ forms the lips and arms of the manubrium are fused
together, and the food, consisting of minute marine organisms, is
taken in through little suctorial mouths and conveyed up long
canals. Pilema octopus * is fairly common. Specimens often attain
a diameter of two feet. The greenish umbrella has a purple frill-
like margin; there are eight tentaculo-cysts with their special
lappets, but there are no tentacles round the margin of the
umbrella. The large mouthless manubrium breaks up into eight
long arms often attaining a length of two feet; the minute,

Case 3,
Upright part.

Case 3,
Upright part.

60 GUIDE TO THE CORAL GALLERY.

Case 3, almost microscopic suctorial mouths armed with fine tentacles
Upright part. (Fig, 240) are abundant in the cauliflower-like regions of the arms.
Very commonly small fish are found associated with the larger
Medusz, which doubtless shelter their protégés and enable them to
dodge out of the way of their enemies. The majority of known
Meduse do not live at any great depth, but a few forms inhabit
the deeper zones of the ocean.

Hicaoas

Pilema, a Rhizostome Medusa. A, entire animal (diminished). B, vertical section.
c, one of the suctorial mouths. c¢, arm canal; gj, gastral filaments; gon, eggs;
or.d, oral arms; rad.c, radial canals; s.mth, suctorial mouths; st, stomach ; é 1, t 2, € 3,

banat onoral arms. (After Cuvier, Claus and Huxley ; from Parker and Haswell’s
oology.

SIPHONOPHORA.

The members of this group are free-swimming colonial Hydrozoa,
in which the individuals composing the colony are modified in
various ways according to the work they perform.

@ase 2) In Physophora (Fig. 240), for example, (see Models and speci-
Upright part. men in Case 3), a hollow stem or siphon is provided at its upper
end with a small air-sac, below which follows series of swimming~

HYDROZOA. 61

bells, medusa-like individuals, each consisting simply of an umbrella, Case 3,
and adapted solely for swimming ; next follows a whorl of leaf-like Upright part.

Fie. 24.

Floating colonies of Siphonophora. a. Diphyes campanulata. B. A group
of appendages from the stem of Diphyes. c (Fig. on right). Physophora
hydrostatica. D. Swimming-bellof the same. x. Cluster of generative
buds (degenerate meduse) of Agalma. a, stem of colony; a’, air
sac; m, swimming-bell; c, concavity of same; v, radial canals;
0, orifice of umbrella; t, covering pieces in B, tentacle-like polypsin c;
n, stomach ; 7, tentacles; g, generative buds. (After Gegenbaur, from
Encye. Britannica.)

“ covering-pieces,” and below this a cluster of medusa-like generative
polyps, tentacle-like polyps and short-stalked feeding polyps, each of

62 GUIDE TO THE CORAL GALLERY.

Case 3, the last having attached to its stalk a long tentacle armed with
Upright part. thread-cells.

In Physalia, the “ Portuguese Man-of-War” (Fig. 25), the air-

iGo.

ne é
Physalia floating on the surface; cr, crest; p, a polyp; pn, air sac. (After
Huxley; from Parker and Haswell’s Zoology.)

sac takes the form of a large pear-shaped bladder provided with a
many-chambered crest ; a mass of generative buds and feeding polyps
with long tentacles is suspended from the under surface of the

HYDROZOA, 63

float; there are no swimming-bells or covering-pieces. Physalia
pelaygica (Model, Case 3) has one long stout main tentacle and
numerous lesser ones; Caravella* (Model, Case 3) has numerous
large tentacles. The float is borne wholly above the surface, and is
carried along by the breeze with the broad end foremost and the
tentacles trailing behind. Prof. Agassiz saw specimens with tentacles
over fifty feet in length. Physalia is notorious for its dangerous
stinging properties.+

Rhodalia miranda* is a deep-sea Siphonophoran, wonderfully
adapted for living at great depths; the depressed oval air-sac is
followed by several circles of swimming-bells each attached by a
broad vertical lamella to the stem.

A curiously modified swimming-bell, the aurophore, allows of
communication between the air-sac and the water; by emptying or
secreting the air or gas the animal can sink or rise within certain
limits without using its swimming-bells. The “stem” is not a
delicate tubular siphon as in Physophora, but forms a thick mass
permeated by canals, the feeding polyps with tentacles and generative
buds being attached to its lower surface.

Most of the swimming-bells and all the tentacles have become
detached in the specimen, the red colour of which is artificial ;
but the air-sac and massive stem are well preserved. ‘The specimens
were obtained by the Challenger from a depth of 600 fathoms in
the South Atlantic.

Diphyes * (Fig. 24 A, B), which is without an air-sac, has two
swimming-bells, and below these groups of covering-pieces, feeding
polyps, and generative buds situated along the stem.

In Velella,* or “ By-the-wind Sailer” (Case 3), a vertical semi-
circular “sail”? is attached diagonally across the upper surface of
an oblong disk ; attached to the lower surface of the latter are one
large central feeding polyp and circles of smaller feeding polyps,
generative buds, and a marginal fringe of tentacles. Fleets of
Velella sailing along in the breeze are more commonly seen in
warm latitudes, but specimens, both of Velelia and Physalia, have
been found off the south-west coasts of England.

Porjita* consists only of a circular disk with its dependent polyps
and tentacles.

' Mrs. David mentions in her book on Funafuti that the natives are more
afraid of Physalia than they are of the sharks.

Case 3,
Upright part.

Case 3,
Upright part.

64 GUIDE TO THE CORAL GALLERY.

CTENOPHORA (COMB-JELLIES).

Case 3, Ctenophora are free-swimming Ccelentera which never form
Upright part. colonies. The body, usually oval or spheroidal, is provided with
eight rows of swimming-plates situated along eight meridians, each

Hie. 26.
cu

Hormiphora plumosa. a, mouth; b, swimming plates. (After Chun.)

plate consisting of a comb-like band of very large cilia. The mouth,
situated at the oral pole, leads into a gullet and stomach, whence
canals proceed to run beneath the swimming-plates; canals also
pass upwards from the stomach to the aboral pole, where they open

HYDROZOA. 65

to the exterior on each side of a centrally-placed “auditory” or
balancing sense-organ.

Some Ctenophorans are provided with a pair of plumose tentacles,
which can be retracted into receptacles. Hormiphora plumosa*
(Fig. 26) has a small pear-shaped body, the mouth being at the
narrow end; the eight rows of swimming-plates occupy about two-
thirds of the length of the body ; a pair of long feathery tentacles
can be emitted from two tentacle-sheaths, which open one on each
side of the body not far from the aboral pole.

Cestus veneris, or “* Venus’ Girdle” * (Fig. 27), has a long band-
shaped body, which may attain a length of several feet ; the mouth
is in the centre of the lower border, and the gullet and stomach
occupy quite a narrow area in the centre of the band; the eight

i tiiveha PAG

Cestus veneris. A,adult. B, young. mth, mouth; ¢, tentacles; lt, lateral
tentacles ; spl', one of the four short rows of swimming plates; sp/l?, one
of the four long rows of swimming plates. (After Chun; from Parker
and Haswell’s Zoology.)

rows of swimming-plates form an apparently continuous line on each
edge of the upper border. The young Cestus is spheroidal, but soon
becomes compressed in a vertical plane and lengthened out.

Cestus swims mainly by the wavy and serpentine motion of its
body. The small exhibited specimen shows the aboral border, with
its apparently continuous rows of swimming-plates nearest the front
of the glass.

Beroé ovata* from Naples is in the form of a large sac with a
wide mouth ; the cavity of the sac is, strictly speaking, the gullet,
the stomach occupying only a small space at the base.

Beroé ovata can alter its shape to a remarkable extent while
swimming, being now V-shaped with widely-gaping lips, now
U-shaped ; the creature is extremely voracious, and can take into its

FE

Case 3,
Upright part.

Case 3,
Upright part.

66 GUIDE TO THE CORAL GALLERY.

Case 3, capacious gullet animals that at first sight appear bigger than
Upright part. jtgelf.

The Ctenophora are now usually regarded as a distinct class of
Ceelentera.
CLASSIFICATION OF HypRoz0a.
(From Prof. Lankester’s Article Hydrozoa, Encyclopedia Britannica.)

Crass Hyprozoa.

| |
Sub-class Hydromedusz Sub-class Scyphomedusza

| | i | | |
Orders Gymnoblastea Calyptoblastea Trachomeduse. Narcomedusx. Hydrocoralline. Siphonophora.
or Athecata. or Thecaphora.

[The Coelentera have been divided, in the various recent classifi-
cations, into two classes, Hydrozoa and Anthozoa; into three,
Hydrozoa, Anthozoa, and Ctenophora; or, again, into four,
Hydrozoa, Scyphozoa, Anthozoa, and Ctenophora. |

COGS)

ANTHOZOA.

The existing Anthozoa are constructed on one of two types ;
they either have eight tentacles and no more, or, like the common
Sea-Anemone, they have a number of tentacles. Where there are
only eight tentacles, as in the noble red coral, each is fringed at its
sides, or, in technical terms, is pinnate; when the tentacles are
numerous they are non-pinnate. A certain number of palaeozoic
corals had a symmetry of four. We may therefore speak of Tetra-
coralla,’ Hexacoralla,? and Octocoralla.?

Both of the latter may have (i.) soft bodies without spicules, (ii.)
horny axes (horny corals), (iii) a continuous limestone skeleton
(stony corals) ; the Alcyonaria may have scattered spicules.

The Hexacoralla, or Zoantharia, commence at the eastern end of
the Gallery, next the Hydrozoa; the Octocoralla, or Alcyonaria,
commence at the western end of the Gallery.

The organisation of the Alcyonaria is illustrated by large
diagrams ; the first, that of Monoxenia darwini, is very possibly only
a larval stage of some Alcyonarian ; but it shows some of the
essential characters of the group. These are a sac-like body, with
an axial gastric cavity, giving off eight compartments, on the
partition walls of which are developed the gonads or reproductive
elements.

The organism seldom remains single; developing a stolon or
creeping process, it gives rise to bud after bud, and so forms a
colony, as in Clavularia (Figs. 1 and 2) or Aleyonium (Fig. 3),
diagrams of which are shown. ‘There are also some excellent water-
colour sketches of Clavularians taken from life, and presented by
Prof. Hickson, F.R.S.

The creeping process or stolon is well seen in the small prepa-
ration of the organ-pipe coral (T’ubipora) ; as shown in Fig. 4, this
is seen to be a small flat plate, from which the tubes are beginning
to rise up.

' Sive Rugosa. ? Sive Zoantharia, % Sive Aleyonaria,

F 2

68 GUIDE TO THE CORAL GALLERY.

The tissues seldom remain soft ; they become impregnated with
horny matter or with carbonate of lime, or both. The horny skeleton
is continuous ; the calcareous consists of separate spicules more or
less closely packed.

The differences at different ages in the amount of lime deposited
are well shown by the fine series of specimens of sis (Case 14).
Colonies formed by budding and provided with a skeleton may
become of great length, as Juncella, or of great intricacy of inter-
lacement, as Gorgonella; often they are of exquisite beauty, as the
Calligorgia from Mauritius (Fig. 5) or the Hookerella from South
Japan suffice to show. Sometimes there is a continuous skeleton, as.
in the noble red coral of the Mediterranean, good specimens of
which, showing the coral polyps expanded, and explanatory diagrams.
of which are exhibited in Case 13.

A particularly dense skeleton is developed in Heliopora (Fig. 6),
the only living member of a group (Coenothecalia) which formed a
large part of the coral fauna of Palaeozoic times. Long considered
to be a Zoantharian, the affinities of Heliopora to the Alcyonaria
were demonstrated by the late H. N. Moseley during the voyage of
H.M.S. Challenger. This skeleton is remarkable for being always of a
plue colour when collected on a reef ; but, as Mr. Stanley Gardiner’s.
collections show, the blue colour gets progressively paler as specimens
are obtained from deeper and deeper water.

In other Alcyonaria a reduction of the skeleton seems to have
occurred, so that the axis is friable and breaks up into scattered
spicules ; this is the case with Paragorgia arborea, a fine example of
which from the coast of Norway is shown with an _ illustrative
drawing as it appears during life, and a well preserved piece with
the polyps partly extended.

In the Pennatulidae reduction goes still farther, and little is left.
in the way of a skeleton save a horny axis, which extends along
the whole of the colony; a striking example is to be seen in the
specimen of Osteocel/a on the south wall of the Gallery.

Fine examples of Pennatula, Funiculina, and others are shown,
as well as two beautiful plates of Umbellula encrinus, taken from the
Report of the Norwegian North Sea Expedition. The curiously
modified and kidney-shaped Renilla should be noticed.

The general plan of the structure of the Octocoralla is shown by
Mr. Berjeau’s water-colour drawing in the Gallery, which is shown,
reduced to a third, in the accompanying figure (Fig. 7), where we
remark the numerous non-pinnate tentacles (¢), the cavities of which

ANTHOZOA. 69

communicate with the general cavity (¢), which is divided into
compartments by septa (7), on the walls of which the gonads (q) are
developed. The axis is occupied by the stomach (s), which com-
municates below with the general cavity, and opens above by a
mouth marked by a special slit (od); p marks the point at which a
chamber is in communication with its neighbour, and d is the lower
surface of the disk.

As it is impossible to preserve in spirit the beauty of form and
colouring presented by Sea-Anemones, the aid of the artist has been
called in, and sketches from life are shown on the walls.

As in the Zoantharia, there may be no spicules, a horny skeleton,
or a continuous calcareous skeleton ; but spicules scattered in the
flesh are not known.

Of the soft-bodied forms other than the well-known Sea-Anemone
of the shore, attention should be directed to the remarkable Ceri-
anthus membranaceus (Fig. 8), which makes for itself a curious woven
tube, open at either end. The effect of this is that, during a
dredging operation, the Cerianthus generally succeeds in making his
escape, and a mere empty tube is all that rewards the dredger.

The Antipatharia have a purely horny skeleton, which encloses a
central canal and is always spiny. This skeleton may be a single
rod, as in Cirripathes, where it may attain a great height, or consist
of a collection of straight rods, as in the remarkable forms from
Mauritius, which has been called Antipathes robillardi; or it
may be more or less branched and form tufts or wide plates, as in
Aphanipathes, or the branches may fuse with one another, as in
Arachnopathes, an elegant example of which will be found by itself
on the wall near the middle doors. The most common form is the
tree-like A. abies (Fig. 9).

According to the recent researches of Dr. Carlgren, the large
black coral-like structure which forms such a conspicuous object
opposite the eastern door to this Gallery, and which is known as
Gerardia savalia (Fig. 10), has been wrongly regarded as an Anti-
patharian or horny coral. It is, according to the Swedish naturalist,
allied by the structure of its polyps to Parazoanthus, and must
therefore be placed with the otherwise soft-bodied Zoantharia. The
specimen here exhibited, with a suitable explanatory label, is sur-
prisingly large, and nothing like it is possessed by any other Museum
of Natural History.

The majority of the specimens belong to the group of stony corals
or Madreporaria. The stoniness is due to the secretion of carbonate

70 GUIDE TO THE CORAL GALLERY.

of lime by the skin of the lower part of the polyp. As the body
grows against this unyielding surface it has to give way, and forms
folds ; the skin of these folds again forms plates of carbonate of
lime ; and thus we get the outer “wall” and the inner septa. The
extent and proportion to which these are developed vary greatly,
especially in the colonial forms. In these the nutrition of the colony
is effected by a system of canals ; the appended figure (Fig. 11) is
Dr. G. H. Fowler’s representation of the canal system of Rhodo-
psammia, When, as in the genus Madrepora and its allies, this system
perforates the substance of the coral (Fig. 12) the coral is said to be
PERFORATE.

The result of budding, long continued and extending layer over
layer, is the formation of large solid masses, which go to form coral
reefs ; the fate of coral masses is well indicated in Case 6B, where the
specimens selected for the Museum by the late Mr. Darwin are
shown. The size to which colonial masses of coral may grow may
be judged from the two enormous specimens of Zwurbinaria peltata,
which cover an area 16 feet and 16 feet 8 inches round, and weigh
12 ewt. and 133 cwt.! respectively (Fig. 13). Sometimes a coral is
by the force of the waves carried away from its resting-place ; if it
be dead, and its substance filled with air, it may float; if so, it will
become, like the large mass of Yavia (Fig. 14) shown at the entrance
to the Shell Gallery, the sport of the waves, and may at last find its
home on an island, where the species to which it belongs is never
found in the living state.

Naturalists experience great difficulty in determining pieces of
coral; the reason for this is to be seen in the photographs of Z'ur-
binaria, where marked differences in appearance (Figs. 15, 16) are
easily apparent. The causes of these differences are seldom easy
to discover, and the guesses of stay-at-home naturalists are of little
service. It seems certain that muddiness of water may be an
important influence, as a deposit of sediment would kill the centre
of a cup-shaped coral; here and there indeed there are indications of
spouts by which water may run off. The extraordinary differences
seen in the large mass of “ Brain coral,’ Maeandrina cerebriformis
(Fig. 17), which is placed in the adjoining corridor, are due, it is
suggested by one experienced in coral reefs, to a marked difference
in the amount of sunlight which could reach the two halves of the
mass.

' 1 cwt. = 112 lbs.’; 60 kilograms is about equal to 1 cwt.

Hrcaele

CLAVULARIA.

CLAVULARIA.

2
Gear

ALCYONIUM.

TUBIPORA.

:
ine
Le

isl
a

CALLIGORGIA.

Fic. 6.

HELIOPORA.

Srcrion oF SEA-ANEMONE.

} a Oe er
| , A 4 The’
x ‘ ¥ -
| coal ae a
Tr te
fi
2 F
i s q
OT ce
‘fy
i i
{
f
”
A,
vt
y
i‘
{
Hy
1
.
Cf
‘
}
dé
“ *
¥
ult cu
ro ;
‘ reba al

The SE

CERIANTHUS MEMBRANACEUS.

J
= va
‘te obama 4
i

; ¥ nehe. -— =
PP RG ts ce ib Sua Ripe Sy wig’ =
a
; ; ¥ ’

fe

tap 1

Fic. 9.

ANTIPATHES ABIES.

os ie pi at

Tl ; Le a

‘ - 6

a
f
- r 4
4
i
*
Z
é
'
-'
1
} fe SR
1
it
r
r
'
t ‘
_ r
1
i ‘ ‘a Pe
Se ny ted
‘ < nary
‘ wee)
i y "
prance We
-)
iv
' a aT |
: . a 2
2 et ten ki

Fig. 10.

=

bs ee oped
— 1 —
< a
=

SSS

ius

MA caval
King
sn

=s

‘ / \ | pp
“il Ne é
(Si
nt hi ven
\ i m VY ) »
UP
U

LJ NY " I
i) \
S, #7.) }

GERARDIA SAVALIA.

(Reduced to one-twentieth natural size.)

MADREPORA.

(‘uosrinduos of ybry sayour g yays sntyneN Y 472A )

ol

‘VLVLIAd VINVNIGYOT,

el “DIA

Fic. 14.

F'AVIA.

TURBINARIA.

%

°
on

16,

Fie.

RBINARIA.

Tt

is
s
: ,
«
AS
iw ete!
’ €
*
LS Ar
, ae 4)
ih. Ps %
. x =!
i ‘ ch 7 \
I
*
'
'
ye
ak
;
‘ ona
.
; i
‘ ls a ;
iy 7
i * i :
‘ a i
2 ah
iy
¢ i ;
och ae
f als [ ¥
= ¥
t ‘A
f f
\ i
&) ;
mt a ¥
1
; t
, '
ai
} "
4 = {
if ; ‘ o
~ a
.
i es
hire
+ BI
~ ‘1 ‘ 2
BS < y
‘y a
7 : 4 -
+ a
t
Hy 7 ee ‘
-- f 7
-
Pete : 4
7 ft a over S
> oa : }
g .
—
_ 4
/ f
? ‘
i gi
Me ,
Le
q ay.
4 Av -

Fig. 17

MAEANDRINA CEREBRIFORMIS,

18.

Fig.

['RIDACOPHYLLIA MANICINA.

r

Fig. 19.

FLABELLUM STOKESI.

Fia. 20.

DESMOPHYLLUM INGENS.

Fic. 21.

BATHYACTIS SYMMETRICA.

ANTHOZOA. 71

Full-grown corals are not always huge masses; they may be of
vreat delicacy and beauty, as is shown by Fig. 18, which represents
Tridacophyllia manicina, and by the three succeeding figures, which
represent various deep-sea corals, Case 88. The discovery of life at
great depths—depths as great as the heights of some of the highest
mountains of the world—was one of the most interesting discoveries
of the second half of the last century, and has led to a great increase
in our knowledge of the globe we inhabit.

Acantharia, 12.
Acinetaria, 14, 19.
Actinophrys, 4, 6.
Actinospherium, 7.
Agalma, 61.
Aglaophenia, 47.
Alicyonaria, 67, 68.
Aleyonium, 67.
Ameeba, 1.
Antennularia, 46, 52.
Anthomeduse, 43, 56.
Anthozoa, 67-71.
Antipatharia, 69.
Antipathes, 69.
Aphanipathes, 69.
Aphrocallistes, 29.
Arachnopathes, 69.
Asconide, 25.
Astylus, 54, 56.
Athecata, 43.
Aulacantha, 14.
Aulosphera, 14.
Aurelia, 58, 59.

Bath sponge, 35.
Bell-animalcule, 17, 18.
Beroé, 65.

Biloculina, 10.

Blood Coral, 54.

Boring sponges, 32.
Bougainvillea, 40, 41,42, 43.

Calcarea, 23, 25.
Calcareous sponges, 23, 25.
Calligorgia, 68.
Campanularina, 45.
Caravella, 63.
Carchesium, 18.
Carmarina, 56, 57.
Carnosa, 25, 31.
Caulospongia, 32.
Ceratella, 45.
Ceratium, 16, 17.
Cercomonas, 15.
Cerianthus, 69.

belt RS) Dal Shige

Cestus, 65.

Chalinid sponges, 34.
Chitina, 45.
Chonelasma, 29.
Choristida, 30.
Ciliata, 14, 18.
Cirripathes, 69.
Chondrilla, 31.

| Chondrosia, 31.

Clathrina, 23, 24, 25.
Clathrulina, 5, 7.
Clavatella, 42, 45.

| Clavularia, 67.

Cliona, 32.
Codosiga, 16.
Coenothecalia, 68.

| Comb-jellies, 40, 64.
| Commercial sponges, 36.
Coral-like Hydrozoa, 40, 47 |

Corallistes, 30.
Cordylophora, 44.
Corticata, 14, 19.
Cotylorhiza, 59.

Covered-eyed Meduse, 55.

Craniella, 29.
Cryptohelia, 54.
Ctenophora, 40, 64.
Cycloclypeus, 9.
Cydonium, 30.

Dendrosoma, 19.
Demospongie, 25, 29.
Dictyonina, 29.
Dictyopodium, 13.
Didymium, 6,
Difflugia, 4.
Diphasia, 38
Diphyes, 61, 63.
Discomeduse, 59.
Distichopora, 54.

| Dorataspis, 13.
| =

Echinonema, 32.
| Esperiopsis, 32.

| Eucyrtidium, 13.
Euplectella, 20, 26, 27.

| Favia, 70.

| Flagellata, 14, 15.
Fleshy sponges, 31.

| Foraminifera, 3, 7.

| Four-ray sponges, 29.
Fresh-water Polyp, 38.
Fresh-water sponges, 32.

| Fuligo, 5.

| Fungus animals, 4.
Funiculina, 68.

| Geodia, 30, 31.
| Geodine sponges, 30.
| Gerardia, 69.
Glass sponges, 24, 26, 27.
Globigerina, 9, 10.
| Globigerina ooze, 10.
Gonium, 15, 16.
Gorgonella, 68.
Grantia, 26.

Gregarina, 14.
Gymnoblastea - Anthome-

duse, 43.

Gymnomyxa, 3.

Halichondria, 20, 21, 22, 23.

Haliclystus, 59.

Haliomma, 11.

Halisarea, 37.

| Heliopora, 68.

Heliozoa, 3, 6.

| Hexacoralla, 67,

| Hexactinellida, 24, 26.

| Hippospongia, 35, 36.
Hookerella, 68.
Hormiphora, 64, 65.

Horny sponges, 25, 34.

| Hyalonema, 28, 29.

| Hydra, 38, 39, 40.

| Hydractinia, 438, 44, 47, 48.

| Hydrallmania, 46.

' Hydrocorallinz, 40, 47, 55.

Hydroida, 40, 55.
Hydroid Zoophytes, 40.
Hydromedusz, 55, 56.
Hydrozoa, 38-66.

TIanthella, 37.
Infusoria, 14.
Isis, 68.

Jelly-fish, 40.
Juncella, 68.

Keratosa, 25, 34,

Lace sponge, 28.
Lagena, 9.
Leptomeduse, 56.
Leucosolenia, 25,
Limnocnida, 56.
Limnocodium, 56,
Lithistid sponges, 30
Lobosa, 3, 4.

Lobster’s Horn Coralline,

46.
Lophocalyx, 29.
Lucernarie, 59,
Luffaria, 37.
Lyssacina, 26.

Madrepora, 70.

Madreporaria, 69.

Maeandrina, 70.

Meduse, 38, 40, 43, 54.

Miliolina, 6,

Millepora, 38, 47, 49, 53,
54, 55, 56.

Monaxonida, 23, 25, 32.

Monaxon sponges,
33.

Monocaulus, 44, 49.
Monbdxenia, 67.
Mycetozoa, 4, 5.
Myxospongida, 25, 37.

Naked-eyed Meduse, 55.
Narcomeduse, 56.
Nassellaria, 13.
Neptune’s Cup, 32.
Neptune’s Trumpet, 37.
Noctiluca, 17.
Nummulites, 9.

LONDON:

DUKE STREET, STAMFORD STREET, S.E.,

25, 32,

-Pheodaria, 14.

| Rhegmatodes, 56.

Rotalia, 9.

| Paramcecium, 19.

INDEX.

Obelia, 46, 50, 56.
Octocoralla, 67, 68.
Osteocella, 68.

Palythoa, 29.
Panda, 56.
Paragorgia, 68.

Parazoanthus, 69.
Parmula, 34.
Pelagia, 59.
Pennaria, 43.
Pennatula, 68.
Pennatulide, 68. |

Phyllospongia, 37.
Physalia, 62, 63.
Physophora, 61, 63.
Pilema, 59, 60.
Plumularina, 45.
Podded Coralline, 47.
Polystomella, 8.
Porifera, 20-37.
Porospora, 14.
Porpita, 63.
Poterion, 32.
Proterospongia, 16,
Proteus animalcule, 1, 2
Protozoa, 1-19.

Radiolaria, 3, 10, 11.
Radiolarian ooze, 10.
Rathkea, 56.
Renilla, 68.

- Reticularia, Tic

Reaphidionkeys: 7.

Rhizopoda, 3, 7.
| Rhodalia, 63.
' Rhodopsammia, 70.

Salpingceca, 16.
Scyphomeduse, 55, 59.
Sea Beard, 46.
Sea-Kidney, 31.
Sea-Nettles, 54.
Semperella, 28.
Sertularia, 38, 45, 46, 51
Sertularina, 45.

Sickle Coralline, 46. |

Silicea, 24.

Simplest animals, 1.

Siphonophora, 40, 56, 60,
61.

| Six-ray sponges, 24, 26.
| Spicules, 27, 28
| Sponges, 20-37.
| Spongia, 34, 35, 36.
| Spongilla, 34.

, 30, 33.

Spongospheera, 12.
Sporozoa, 14.
Spumellaria, 11.

| Squirrel’s Tail Zoophyte,
46.

Stag’s Horn Millepora, 49.
Stentor, 18.

Stylaster, 38, 53.
Stylasteride, 47, 53.
Stylonychia, 19.
Suberites, 32.

_Sun-animaleule, 4, 5, 6.

Sycon, 23, 25.

Tetracoralla, 67.
Tetractinellida, 25, 29.
Tiara, 56.
Thecaphora, 45, 45.
Thuiaria, 46.

Toilet sponge, 35.

Trachomedus®, 56.
Tridacophyllia, 71.
Trumpet Polypus, 18.

'Tubipora, 67.

Tubularia, 43.
Turbinaria, 70.
Turkey sponge, 34.

_ Umbellula, 68.

| Velella, 63.
| Ventriculites, 29.

Venus’ Flower-Basket, 20
96.

Venus’ Girdle, 65.

Volvox, 15, 16.

Vorticella, 17, 18.

Walteria, 28.

Xiphacantha, 12.

Zoantharia, 67, 69.

PRINTED BY WILLIAM CLOWES AND SONS, LIMITED,
AND GREAT WINDMILL STREET, W.

GUIDE-BOOKS.
(To be obtained only at the Museum.)

General Guide to the British Museum (Natural History), 8vo. 5d.

Guide to the Galleries of Mammalia, 8vo. 6d.

Galleries of Reptiles and Fishes, 8vo. 6d.

——- Shell and Starfish Galleries, 8vo. 6d.

———— Coral Gallery, 8vo: 1s.

————— Fossil Mammals and Birds, 8vo._ 6d.

——-—\— Fossil Reptiles and Fishes, 8vo. 6d.

———-—— Fossil Invertebrates and Plants, 8vo., 1s.; or in two

parts, at 6d. each.

- Mineral Gallery, 8vo. 1d.

Index to the Collection of Minerals, 8vo. 2d.

An Introduction to the Study of Minerals, with a Guide to the
Mineral Gallery, 8vo. 6d.

—_—_—_——_—— to the Study of Rocks, 8vo. 6d.

—— to the Study of Meteorites, 8vo. 6d.

Guide to Sowerby’s Models of British Fungi, 8vo. 4d.

— the British Mycetozoa, 8vo. 3d.

CATALOGUES (Selection).

Report on the Zoological Collections made....during the Voyage of
H.M.S. ‘ Alert,’ 1881-82. Plates. 1884, 8vo. £1 10s.

A Monograph of Christmas Island (Indian Ocean). Woodcuts and
Plates. 1900, 8vo. 20s.

Catalogue of Monkeys, Lemurs, and Fruit-eating Bats. Woodcuts.
1870, 8vo. 4s.

Carnivorous Mammalia. Woodeuts. 1869, 8vo. 6s. 6d.
Seals and Whales. 2nd edition. Woodcuts. 1866,
8vo. 8s.
—_—_—_—___--——_—_—__———. Supplement. Woodcuts. 1871,

8vo. 2s. 6d.
List of the Specimens of Cetacea. 1885, 8vo. 1s. 6d.
Catalogue of Ruminant Mammalia (Pecora). Plates. 1872, 8vo.
38. 6d.

—————— Marsupialia and Monotremata. Plates. 1888, 8vo.
£1 8s.

Birds. Vols. VI-XXVII. Woodcuts and Coloured
Plates. 1881-99, 8vo. 14s. to 36s. a volume.

Hand-list of Birds. Vols. I-III. 1899-1901, 8vo. 10s. each.

Catalogue of Birds’ Eggs. Vols. I., II. Coloured Plates. 1901-2,
8vo. 30s. each.

CATALOGUES (Selection)—continued.

Catalogue of Chelonians. Woodcuts and Plates. 1899, 8vo. 15s.

; Lizards. 2nd edition. Vols. I-III. Plates. 1885-87,
8vo. 20s. to 26s. each.

————— Snakes. Vols. I-III. Woodcuts and Plates. 1893-96,

8vo. 17s. 6d. to £1 6s. each.
————— Fishes. 2nd. edition. Vol. I. Woodcuts and 15
Plates. 1895, 8vo. ‘15s.
Spiders of Burma. 1895, 8vo. 10s. 6d.
Monograph of the Culicide, or Mosquitoes. Woodeuts and Coloured
Plates. 3 vols. 1901, 8vo. £3 3s.
Catalogue of Moths (Lepidoptera Phalanze). Woodcuts and Coloured
Plates. Vol. I., Syntomide. 1898, 8vo. Text 15s.
Plates 15s. Vol. II., Arctiadee (Nolina, Lithosiane).
1900, 8vo. Text 18s. Plates 15s. Vol. III,
Arctiadee (Arctiane) and Agaristide. 1901, 8vo.
Text 15s. Plates 16s.

————— British Hymenoptera. 2nd edition. Pt. I. New Issue.
Plates. 1891, 8vo. 6s.

——_——— British Echinoderms. Woodcuts and Plates. 1892,

8vo. 12s. 6d.

————— Madreporarian Corals. Vols. I-III. Plates. 1893-97,

4dto. 18s. to 24s. a volume.

Hlustrations of the Botany of Captain Cook’s Voyage round the
World in H.MLS. ‘ Endeavour’ in 1768-71. Pt. I. 101 Copper-
plates. 1900, fol. 25s. Pt. II. 142 Copper-plates. 1901, fol.
3D8.

Catalogue of African Plants. Vol. I. in 4 parts. 1896-1900, 8vo.
4s. to 7s. 6d. a part. Vol. II. in 2 parts. 1899-1901, 8vo. 6s.
a part.

Monograph of British Lichens. Part I. 74 Woodcuts. 1894, 8vo. 16s.

the Mycetozoa. 78 Plates and 51 Woodeuts. 1894,
8vo. 15s.

The above-mentioned Catalogues can be purchased of Messrs.
Lonemans & Co., 39 Paternoster Row; My. Quarircn, 15
Pweadilly ; Messrs. Kegan Paun, Trencu, Trisner & Co.,
Paternoster House, Charing Cross Road ; and Messrs. Duna & Co..
37 Soho Square; or at the Naruran History Museum, Cromwell
Road, London, S.W. A more detailed list can be obtained on
application to the Director of the Museum.

BRITISH MUSEUM |
(NATURAL HISTORY). “re

DAYS AND HOURS OF "ADMISSION. os |

The Exhibition Galleries are open to the Public, free, eve
week-day in |

January, from 10 am. till 4 P.M.
February, ikea ae AOR ae
March, agg i ap haa
April to August, da dal phe ae
September, Aa ERS uN Mine ih ot
October, MOM pry Ah
November and December, Sed ash ocala RA en as

Also, from May 1st to the middle of July, on Mondays and
Saturdays only, till 8 p.m.,

and from the middle of July to the end of August, on Mondays:
and Saturdays only, till 7 p.m.

The Museum is also open on Sunday afternoons throughout
the year.
The Museum is closed on Good-Friday and Christmas Day.

By Order of the Trustees,

E. RAY LANKESTER,
Director.

LONDON: “PRINTED BY WILLTAM CLOWES AND SONS, | LIMITED, DUKE STREET, STAMFORD 2D STREET, ‘8 Ey
AND GREAT WINDMILL STREET, W.