of all the marine snail shells, the common 

 black whelk (Nassa obsoleta) being the 

 most common of all the mollusks. The 

 writer has seen a mud flat at low water 

 literally paved with the shells of this snail, 

 there being millions of the little crea- 

 tures crawling about. The shells of this 

 family are frequently very handsome, be- 

 ing latticed by the crossing of lateral and 

 longitudinal lines. They are mostly of 

 small size, scarcely exceeding an inch in 

 length, many of them being much under 

 these dimensions. The animal is very 

 rapid in movement and leaves a distinct 

 track in the mud, which will frequently 

 end at a little pellet of mud, which, upon 

 examination, will disclose the little ani- 

 mal nicely concealed beneath. 



The Nassas of France are very de- 

 structive to the oyster beds of that na- 

 tion, an adult "borer" being able to per- 

 forate the shell of a large oyster in a sin- 

 gle night. So numerous are these pests 

 that a single acre has yielded over a thou- 

 sand individuals. As a result of these 

 depredations the French oystermen carry 

 on a relentless war against the Nassa, de- 

 stroying thousands of animals annually. 

 With all this persecution the mollusk still 

 exists and even increases in numbers. 

 The dead shells of this genus are a fa- 

 vorite home for the hermit crabs of small 

 size, and it is to be suspected sometimes 

 that other than dead shells are appro- 

 priated. We fear that a sort of piracy is 

 resorted to by the hermit crab, resulting 

 in a kind of "walk-the-plank" end for the 

 mollusk, before the new tenant takes pos- 

 session of the "home." 



Of the many varieties of tropical shells, 

 few exceed the Volutes, or bat shells, in 

 beauty or variety of coloration. They 

 are found in most parts of the world, al- 

 though strangely enough none are now 

 living in the seas of Europe, but they are 

 most abundant and more highly colored 

 in the tropics and subtropics. The ani- 

 mal is carnivorous, and the long, fang- 

 shaped teeth are certainly suggestive of 

 predaeeous habits. The shells are vari- 

 ously colored, some being mottled, some 

 with zigzag or lightning-like markings, 

 while others have spirally arranged dots 

 and lines. One species (Voluta musica, 

 figured on the plate), has received its 

 name from a more or less fanciful resem- 



blance of the surface of the shell to a mu- 

 sical staff, the spiral lines being grouped 

 in sets of four or five and the dots being 

 arranged as notes. In some specimens 

 this resemblance is quite close. The 

 smooth and polished shell of some vol- 

 utes is due to the fact that the greater 

 portion is covered by a reflected part of 

 the large foot. 



On the sandy shores of subtropical 

 beaches certain graceful and polished ani- 

 mals bury themselves from sight in the 

 sand. These are the olive shells (Oliva) 

 whose bright colors and highly polished 

 surfaces rival even the gaudy Volute in 

 beauty. The foot may be described as 

 plough-shaped and is admirably adapted 

 for digging rapidly in the sand, so that 

 the shell may be hidden from sight on the 

 approach of enemies. The long siphon is 

 thrust up through the canal in the an- 

 terior part of the shell and its end pro- 

 trudes above the sand. The high polish 

 of the surface is due to the shell being 

 enveloped in the voluminous foot; hence 

 it has no epidermis. The aperture is so 

 narrow that it is difficult to understand 

 how the animal gets in and out. The 

 olives are very numerous in individuals; 

 when one is found hundreds are sure to 

 reward a patient search. 



Probably no more distinct family of 

 mollusks exists than the Conidae, the 

 family of cones, their beautifully deco- 

 rated shells and the large number of spe- 

 cies making them a favorite with collect- 

 ors. The shell is in the form of an invert- 

 ed cone, gracefully rounded, the aper- 

 ture being but a narrow slit extending 

 nearly the whole length of the shell. The 

 colors of the cones are always very bril- 

 liant, although when they are alive the 

 shell is not brilliantly polished as the 

 olives, on account of the presence of an 

 epidermis. About three hundred species 

 are known, living principally in tropical 

 seas. They love to conceal themselves in 

 holes in the rocks and among the 

 branches of corals. The animal is pre- 

 daceous, boring into the shells of other 

 mollusks and extracting the juices from 

 the bodies. The teeth of Conus are hol- 

 low and very sharp and have a barb on 

 the end. A poison gland is said to be 

 present in this genus and bites from the 

 animal are very painful, although not 



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