THE SEA-SNAILS. 693 



to commerce. A large portion of them carry under the skin of the back a long, flat, calcareous 

 "bone" or plate, which serves as a stay or support to the frame in lieu of a skeletou. In some 

 species it is long and slender like a quill-pen. This bone, reduced to powder, forms a useful 

 pounce, " used in rewriting over erasures to prevent blotting, and in medicine as an antacid." It 

 is also combined into a dentifrice. The principal use for it, nevertheless, is for feeding to caged 

 birds requiring lime for their health. For this purpose several hundred- weight of "cuttlebone" 

 are brought into the United States annually. It is furnished chiefly from Chinese waters, 

 but is also collected floating in the Mediterranean. None of our American species alford a useful 

 cuttle-bone, however; so that this import can scarcely be diminisheJ. The name "Oalamary" 

 is often applied to a Cuttle-fish, and arises from the fact that each of them carries in an internal 

 gland a supply of blue-black, ink-like liquid, which upon the slightest alarm he discharges into 

 the water, making a dense cloud under cover of which he rapidly retreats.' This ink, removed and 

 dried into little cakes, with a greater or less adulteration, forms the sepia of painters and the 

 India ink of draughtsmen. Now it is brought almost wholly from Oriental ports, via London, 

 but it might probably be saved on our coast as well. Provided with pen and ink on all occa- 

 sions, these moUusks seem truly to stand at the head of the class of animals they represent — 

 not wholly because of their superior size and loftier brain and organization, but also on the score 

 of literary accomplishments. 



206. THE SEA-SNAILS— GASTEROPODA. 



The Gasteropod mollusks, bearing a shell in a single piece and usually spirally whorled, are 

 not of much direct utility to man, as a rule, on this side of the world, north of the tropics ; but there 

 are a few species which deserve mention. Their principal claim to notice in Ibis connection lies 

 in the fact that they figure upon the habitual bill of fare of various fishes. No doubt the list 

 appended might be greatly enlarged if we were better informed, particularly in respect to the 

 southern coast. Thus far the chief knowledge possessed in respect to the molluscau food of 

 American fishes is derived from Gould's " Eeport upon the Invertebrates of Massachusetts," and 

 Prof. A. E. Verrill's report to the United States Fish Commission. From this and other sources 

 is compiled the succeeding catalogue of species of Gasteropod mollusks that are fed upon by 

 fishes; these, it must be observed, are confined to the Atlantic coast, and, to a great extent, to the 

 waters of New England, through lack of information in respect to the similar food of the fishes of 

 the southern and the western coast. The list includes about fifty species, and reads : 



Bela turricula, Bela harpularia, Bela pyramidalis, Bela decitssata, Admete Gouthouye, Weptunea 

 despecta, Buceinum undatum, Buccinum ciliatum, Tritia trivittata, llyanassa obsoleta^ Trophon 

 clatliratus, Trophon clathratus var. scalar if or mis, Purpura lapillus, Astyris rosacea, Astyris lunata, 

 Natica clausa, Lunatia heros, Lunatia grcenlandica, Lunatia immaculata, Amauropsis islandica, 

 Velutina zonata, Velutina Icevigata, Lamellaria perspicua, Littorina — several species, Triforis nigro- 

 oinctm, Bittimm nigrum, Turritella erosa, Tricholropis borealis, Grepidula fornicata, Grepidula plana, 

 Aporrhais occidentalis, Scalaria grcenlandica, Scalaria Novanglice, Margarita cinerea, Margarita 

 grcenlandica, Margarita argentata, Machceroplax obscura, Puncturella noachina, Tonicella marmora, 

 Trachydermon albus, Trachydermon ruber, Chiton — various species. Auricula vestita var. Emersonii, 



'There are frightful tales abroad of the ferocity with which the larger of these creatures will attack man, and they 

 are greatly dreaded by the shell-divers of the South Seas; but the truth is the Cuttle-fish is timid, and will hide or run 

 away whenever he can from anything so large and strange as a man; that is, any Cuttles smaller than the giants of 

 Newfcundlaiid. A diver who touched a large Octopus would instinctively be seized, of course, since the creature would 

 know no different course of action; but voluntary attack is not credited by those who know most about the habits of the 

 animal. 



