188 ANIMALS OF THE SEASHORE 



Nassa trivittata Say (Sand Flat Snail; White 



Mud Snail) 

 ( Nassarius trivittata Say; Tritia trivittata Say ; Alectrion 

 trivittata Say) 



PLATE XVIII. Fig. 6 



About the size of N. dbsoleta, but white and 

 granulated in appearance. Common on sandy shores 

 from just below low tide to fathoms; more common 

 in the open ocean than in the inlets and bays al- 

 though it is frequent in parts of Delaware Bay. 

 Shells of this and the above species, often inhabited 

 by Hermit Crabs are very abundant in tide pools 

 and washed up on the beaches. Known from the 

 Gulf of St. Lawrence to Florida. 



Nassa vibex Say (Southern Mud Snail) 



PLATE XX. Fig. 5 



This species is not common north of Cape 

 Charles, Virginia. It has, however, been collected 

 alive from the New Jersey coast and as far north 

 as Vineyard Sound, Massachusetts. The shell is 

 slightly smaller than the two preceding species and 

 is white with brownish spots. It is very common 

 in sandy bays along the Florida coast; known from 

 the Pleistocene deposits of New Jersev. 



