FIELD BOOK OF PONDS AND STREAMS 



water plants. They will eat greedily of bits of meat, pieces 

 of earthworm, and water insects but they should not be fed 

 up to the demands of their appetites. 



Cambarus bartoni. — This is the commonest crayfish in the 

 eastern states, being found in small quiet streams from Tennes- 

 see and the Carolinas to Maine. It can be distinguished by 

 the smooth carapace of both sexes (Fig. 133) and the hooks 

 on the first pair of abdominal appendages of the male. Length, 

 3 inches. 



Fig. 134. — Spiny crayfish, Cambarus limosus, 

 :howing spines on the carapace. 



Cambarus limosus (C. affinis). — The carapace is spiny in 

 both sexes and the body is sparsely covered with hairs (Fig. 

 134). In the male the first pair of abdominal appendages 

 are straight. Length about 4 inches. 



Occurrence. — In rivers and ponds of New York, Pennsyl- 

 vania to Virginia. 



Chimney crayfishes, Cambarus diogenes. — These crayfishes 

 are real chimney-builders which make burrows two or three 

 feet deep in the stream banks. They dig out chambers in 

 the lower parts of these, which fill with water and make safe 

 retreats. Turrets several inches high are built around the 

 upper openings of the burrows which may be a foot or more 

 back from the stream. Length about 4 inches. 



Occurrence. — Locally common especially in quiet streams, 

 east of the Rocky Mountains to the Atlantic Coast. 



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