THE BASKET SHELL. 37 



breathing tube which projects above the surface of the 

 mud which the animal is exploring for its prey. 



The Nassas are active mollusks, and are cordially 

 hated by the oystermen, because they are so fond of 

 boring a hole through the shells of young oysters 

 and eating the contents with as much relish as any 

 other judge of good living. They bore into various 

 clams, too, and it is even hinted that they sometimes 

 attack their own kind. But they are scavengers also, 

 and consume the flesh of dead crabs and like animals 

 which are so liable to be found near the shores. I 

 have some beautiful specimens of this species which 

 were taken from the stomach of a large fish, showing 

 that the biter of other animals is liable to be swallowed 

 whole when the avenging and hungry fish comes 

 round. The length of an adult shell is about an inch 

 and a half, and is seldom as much as two inches. 

 Nassa tegida, Rve., teg'-u-la, shown in Fig. 17, is 

 a southern species. Shell, strong ; spire, 

 conical, half the length of the whole shell, 

 and marked with little knobs ; aperture, 

 small ; canal, reflexed ; inner lip covered 

 with a large callus of smooth, white enamel. 

 Color, dark gray ; length, three-fourths of 

 Fig. 17. an inch. 



Nassa mendica, Gld., men'-di-ca, Fig. 18, is a vari- 

 able species, having a shell about the length 

 of the last one, but more slender. The sur- 

 face is marked by numerous fine spiral lines, 

 crossed by ridgy varices. It is light brown in 

 color, with a white peristome, or margin of 

 the aperture. It occurs all along the coast 

 from Puget Sound to San Diego. 

 Nassa Cooperi, Fbs., Coop'-er-i, which has seven 



