information relative to the characteristics of the bottom (whether 

 sandy, muddy, gravelly, or weedy), the date, the depth, and any other 

 items of interest. It is desirable that each haul of the dredge be kept 

 separate, and for this purpose several tubs, or other receptacles, will 

 be found necessary. A fine wire sieve will be found useful in washing 

 the material. 



" Every variety of shore supports a certain type of mollusk, which 

 also varies in different latitudes. Thus a rocky shore is especially 

 adapted for Chitons, limpets, and periwinkles, and a sandy beach is 

 the favorite home of the Naticas, or moon shells, the JVassas, or basket 

 shells, and the large Fidgur, or winkle shell, and of course the bivalves 

 specially abound in muddy and sandy beaches. 

 In tropical regions the coral reefs are fairly 

 alive with mollusks. The student must learn 

 by experience just what species live in each 

 kind of a locality." 



Having rested ourselves, w r e now removed 

 our shoes and stockings, rolled up our trousers, 

 and walked toward the water, determined to 

 thoroughly explore the shore for mollusks. 

 When about half-way across the beach, Harry 

 found a horse-foot crab, the outside and inside 

 of whose shell was covered with rounded, flat- 

 tened shells. Professor Parker said that these 

 were the slipper shells, or Crepididas, and we 

 proceeded to strip the crustacean of every one 

 of its ornaments, and no less than a hundred 

 shells of various sizes were taken from this crab. 



We soon reached the rocky shore which the 

 tide had left uncovered, and each of us began to eagerly search for shells. 

 The rocks were slippery, and covered with great masses of seaweed, 

 while the little pools left in the hollows were rilled with the most gor- 

 geously colored weeds green, red, and pink - - which waved gracefully 

 about in the eddying waters. The rocks were tenanted by millions of 

 the periwinkles, whose shells of black, yellow, and red seemed to be every- 

 where. The purple shells (Purpura) were also very abundant, and George 

 was fortunate enough to find several limpets neatly tucked away on the 

 under side of an overhanging rock. Some of the seaweed was filled 

 with the minute shells of Cerithium, and the little pools contained sev- 

 eral specimens of the naked sea slugs (Doris). The sea slugs were very 

 curious, with their peculiar shapes, brilliant colors, and odd, plume-like 



91 



Fulgur canaliculatus, the 

 common winkle shell of the 

 New England states. (Dall.) 



