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they are probably analogous to the birds' heads in the Cellularae。
PLATE V。
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CORALS AND SEA ANEMONES。
CARYOPHYLLAEA SMITHII。 PL。 V。 FIG。 2。 PL。 VI。 FIG。 3。
THE connection between Brainstones； Mushroom Corals； and other
Madrepores abounding on Polynesian reefs； and the 〃Sea Anemones；〃
which have lately become so familiar to us all； can be seen by
comparing our comparatively insignificant C。 Smithii with our
commonest species of Actinia and Sagartia。 The former is a beautiful
object when the fleshy part and tentacles are wholly or partially
expanded。 Like Actinia； it has a membranous covering； a simple sac…
like stomach； a central mouth； a disk surrounded by contractile and
adhesive tentacles。 Unlike Actinia； it is fixed to submarine bodies； to
which it is glued in very early life； and cannot change its place。 Unlike
Actinia； its body is supported by a stony skeleton of calcareous plates
arranged edgewise so as to radiate from the centre。 But as we find
some Molluscs furnished with a shell； and others even of the same
character and habits without one； so we find that in spite of this
seemingly important difference； the animals are very similar in their
nature。 Since the introduction of glass tanks we have opportunities of
seeing anemones crawling up the sides； so as to exhibit their entire basal
disk； and then we may observe lightly coloured lines of a less
transparent substance than the interstices； radiating from the margin to
the centre； some short； others reaching the entire distance； and arranged
in exactly the same manner as the plates of Caryophyllaea。 These are
doubtless flexible walls of compartments dividing the fleshy parts of the
softer animals； and corresponding with the septa of the coral。 Fig。 2 A
represents a section of the latter； to be compared with the basal disk of
Sagartia。
SAGARTIA ANGUICOMA。 PL。 V。 FIG。 3； A； B。
This genus has been separated from Actinia on account of its habit
of throwing out threads when irritated。 Although my specimens often
assumed the form represented in fig。 3； Mr。 Lloyd informs me that it
must have arisen from unhealthiness of condition； its usual habit being
to contract into a more flattened form。 When fully expanded； its
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transparent and lengthened tentacles present a beautiful appearance。
Fig。 3 A； showing a basal disk； is given for the purpose already
described。
BALANOPHYLLAEA REGIA。 PL。 V。 FIG。 1。
Another species of British madrepore； found by Mr。 Gosse at
Ilfracombe； and by Mr。 Kingsley at Lundy Island。 It is smaller than O。
Smithii； of a very bright colour； and always covers the upper part of its
bony skeleton； in which the plates are differently arranged from those of
the smaller species。 Fig。 1 shows the tentacles expanded in an unusual
degree； 1 A； animal contracted； 1 B； the coral； 1 C； a tentacle enlarged。
PLATE VI。
CORALS AND SEA ANEMONES。
ACTINIA MESEMBRYANTHEMUM。 PL。 VI。 FIG。 1 A。
This common species is more frequently met with than many others；
because it prefers shallow water； and often lives high up among rocks
which are only covered by the sea at very high tide； so that the creature
can； if it will； spend but a short portion of its time immersed。 When
uncovered by the tide； it gathers up its leathery tunic； and presents the
appearance of fig。 1 A。 When under water it may often be seen
expanding its flower…like disk and moving its feelers in search of food。
These feelers have a certain power of adhesion； and any not too vigorous
animals which they touch are easily drawn towards the centre and
swallowed。 Around the margin of the tunic are seen peeping out
between the tentacles certain bright blue globules looking very like eyes；
but whose purpose is not exactly ascertained。 Fig。 1 represents the disk
only partially expanded。
BUNODES CRASSICORNIS。 PL。 VI。 FIG。 2。
This genus of Actinioid zoophytes is distinguished from Actinia
proper by the tubercles or warts which stud the outer covering of the
animal。 In B。 gemmacea these warts are arranged symmetrically； so as
to give a peculiarly jewelled appearance to the body。 Being of a large
size； the tentacles of B。 crassicornis exhibit in great perfection the
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adhesive powers produced by the nettling threads which proceed from
them。
CARYOPHYLLAEA SMITHII。 PL。 VI。 FIG。 3。
This figure is to show a whiter variety； with the flesh and tentacles
fully expanded
PLATE VIII。
MOLLUSCA。
NASSA RETICULATA。 PL。 VIII。 fig。 2； A； B； C； D； E； F
A VERY active Mollusc； given here chiefly on account of the
opportunity afforded by the birth of young fry in Mr。 Lloyd's tanks。
The NASSA feeds on small animalcules； for which； in aquaria； it may be
seen routing among the sand and stones； sometimes burying itself among
them so as only to show its caudal tube moving along between them。 A
pair of Nassae in Mr。 Lloyd's collection； deposited； on the 5th of April；
about fifty capsules or bags of eggs upon the stems of weeds （fig。 2 B）；
each capsule contained about a hundred eggs。 The capsules opened on
the 16th of May； permitting the escape of rotiferous fry （fig。 2； C； D； E）；
not in the slightest degree resembling the parent； but presenting minute
nautilus…shaped transparent shells。 These shells rather hang on than
cover the bodies； which have a pair of lobes； around which vibrate
minute cilia in such a manner as to give them an appearance of rotatory
motion。 Under a lens they may be seen moving about very actively in
various positions； but always with the look of being moved by rapidly
turning wheels。 We should have been glad to witness the next step
towards assuming their ultimate form； but were disappointed； as the
embryos died。 Fig。 2 F is the tongue of a Nassa； from a photograph by
Dr。 Kingsley。
Footnotes：
（1） SERTULARIA OPERCULATA and GEMELLARIA
LOCICULATA； or any of the small SERTULARIAE； compared with
CRISIAE and CELLULARIAE； are very good examples。 For a fuller
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description of these； see Appendix explaining Plate I。
（2） If any inland reader wishes to see the action of this foot； in the
bivalve Molluscs； let him look at the Common Pond…Mussel （Anodon
Cygneus）； which he will find in most stagnant waters； and see how he
burrows with it in the mud； and how； when the water is drawn off； he
walks solemnly into deeper water； leaving a furrow behind him。
（3） These shells are so common that I have not cared to figure them。
（4） Plate IX。 Fig。 3； represents both parasites on the dead Turritella。
（5） A few words on him； and on sea…anemones in general； may be
found in Appendix II。 But