32 The Rev. L. Guitp1ne on Naticina and Dentalium, 
having been contracted from immersion in spirit, did not enable him to com- 
plete his history of the animal, and it is probable much will remain to be 
noticed till we can obtain the inhabitants of some of the larger shells. Having 
lately dredged up a small specimen about -2,ths of an inch long, I hastened to 
make a highly magnified figure of it before its death, and my trifling addition to 
the memoir of M. Deshayes is now offered to the Linnean Society, not without 
the hope that my description may soon be rendered more perfect by the aid of 
larger specimens. The minuteness of the example I obtained did not allow 
me by dissection to ascertain many particulars recorded in the memoir alluded 
to. The head, jaws, mouth, and lips, the muscular ring of adhesion, the anal 
funnel-shaped expansion, and the horse-shoe cicatrix on the shell, escaped my 
notice. What M. Deshayes has described as the liver, I should rather suppose 
to be the branchize, notwithstanding their unusual livid colour. These organs 
are regularly and deeply pectinated, and resemble a long-handled comb. The 
numerous elongate subcapitate anterior organs I would call tentacula: their 
extremities appear to be suctorious. Whether the convex side is properly called 
the back I did not determine; my specimen certainly drew itself along on its 
side, but this may have been owing to the shallow layer of sand in which it 
endeavoured to bury itself in the soup-plate which contained it, where it might 
not have been able to assume its proper attitude. From residing under the 
loose sand, their shells are of course free from extraneous matter, though not 
shielded by the pallium. The creature moves tolerably quick by sudden in- 
terrupted steps. When disturbed, it retreats quickly into its shell, which has 
no operculum as the Serpulide. After a time the cloak is protruded, the ten- 
tacula set in motion, and the vermiform active foot partially thrust out to 
explore its path, as at Tas. III. fig. 1.: when it wishes to proceed apace, the foot, 
with its petal-shaped alz closed round the stem, is protruded to its full length, 
as at fig. 3.: the ale are then suddenly expanded, as at fig. 4.; and the base 
of the foot being forcibly contracted, the shell is brought forward, while these 
expansions laid open in the sand prevent the apex of the foot from losing its 
advanced position. In drawing up descriptions, we must be careful how we _ 
speak of the absence of the anal fissure or rima. In recent specimens the apex 
is often produced to a very fine thin point, which with the whole fissure is 
very easily worn off, and seldom likely to occur in fossil examples, or shells 
