MOLLUSCS, OR SHELL-FISH. 245 



and clumsy. The other species of Fusus, F. islandicus, is 

 much smaller and more distinctly spindle-shaped; the two 

 species may be recognised and distinguished by the following 

 characters. In the larger species the surface of the shell is 

 covered by numerous strong striae placed very close together. 

 The mouth is very large, being longer than the spire, and 

 about twice as long as it is broad. The result is to produce 

 a shell which is very wide at its lower part and only tapers 

 very gradually above. In Fusus islandicus the surface is 

 covered by relatively few strise, separated from each other 

 by an interval broader than they are themselves. The 

 mouth is not so long as the spire, and the breadth is only 

 about a third of the length. In consequence the body- 

 whorl is narrow, and tapers suddenly to a somewhat sharp 

 point. 



The only other of these Gasteropods we shall mention is 

 that curious little one known as the " blackamoor's tooth," 

 or cowry, which is so common on the beach, and is so often 

 collected in hundreds by enthusiasts who spend the greater 

 part of their summer holiday poring over the beds of 

 gravel in which the little shells are found. I have often 

 wondered whether the results in the shape of long necklaces 

 of perforated shells are worth the labour and the backaches 

 of the gathering. The living animals, however, are exceed- 

 ingly interesting, and may sometimes be found on the rocks 

 near low-tide mark. When fully expanded two bright 

 orange folds envelop the shell so as to almost conceal it. 

 The tentacles are very long, and, like the rest of the head, 

 the foot and the siphon, are of a pale yellow colour. When 

 very young the shell is coiled as in most Azygobranchs, but 

 as it grows the spire is concealed by the growth of the 

 body-whorl, and the inflection of the lip produces the long 

 narrow aperture so characteristic of the cowries, to which 

 family the present form the Cyprea europcea of systematists 

 belongs. The living animal is a most gorgeous little 

 creature, the prevalent orange tint being often set off by 

 bands and markings of other colours, or replaced by a 

 pinkish colour. The shell is quite white, as is often the 

 case with concealed shells. 



