704 
MR. S. J. HICKSON ON THE CILIATED GROOVE 
IS. Milne Edwardes. ‘ Histoire naturelle des Corallaires.’ Paris : 1867. 
19. S. O. Ridley. “Account of the Zoological Collections made during the Survey 
of H.M.S. ‘Alert’ in the Straits of Magellan and on the Coasts of Patagonia.” 
Proceedings Zoological Society, 1881. 
20. P. Wright. “ Hartea elegans.” Quarterly Journal Microscopical Science, 1865. 
Description of the Plates. 
The following lettering is used throughout. 
st. Stomodseum. 
si. Siphonoglyphe. 
siph. Siphonozooid. 
ciut. Autozooicl. 
m.f. Mesenterial filament. 
sp. Spicules in the body-wall. 
sp'. Spicules in the walls of the stomodseum. 
sp' . Spicules in the sarcosoma. 
c. c. Gastrovascular canals. 
ep. Epithelium. 
p. Used in figs. 11 and 12 for the spaces left after the skeletal plates have been 
dissolved in acid. 
ov. Ova. 
t. Tentacles. 
v. Ventral side. 
d. Dorsal side. 
Fig. 1. A diagrammatic sketch of a longitudinal section through a polyp of Alcyonium 
digitatum , showing the wall of the siphonoglyphe on the ventral side with 
its long cilia pointing towards the body cavity, and the wall of the 
stomodeeum on the dorsal side, which is not so thick, and beset with hut 
small cilia. The arrows indicate the directions the currents of water take 
in a living polyp. 
Fig. 2. Transverse section through a polyp of Alcyonium palmcitum in the middle 
region of the stomodseum. The siphonoglyphe is seen on the ventral side 
of the stomodceum, armed with its long cilia, and in its substance are seen 
imbedded the long spicules. 
Fig. 3. Transverse section through a polyp of Ccclogorgia pulmosa. The lumen of the 
stomodseum is seen to be " 7 " -shaped in section, the cross portion of the T 
forming the siphonoglyphe is armed with long, delicate cilia, and the rest 
of the stomodeeum with short, dense cilia. 
Fig. 4. Transverse section through an autozooid of Scircophyton puhno (semi- 
