FRESH-WATER MALACOSTRACA OF ONTARIO 

 SESSIONAL PAPER No. 39b 



159 



greater than breadth (in C. hartonii it is only two-thirds of breadth). Areola 

 not entirely obliterated at any point, but nearly so. The excavation at the base 

 of the movable finger of the large chelae enables one to readily recognize this species. 



Fig. 11. 



Faxon apparently had no knowledge of Cottle's article. The description of 

 Cottle leaves no doubt as to the identity of his species with that of Faxon. Cottle 

 gives an account of the burrowing habit and of the duration of the spawning period. 



Cambarus diogenes Girard. Fig. 11, b. 



C. ohesus Hagen, p. 81. 



C. diogenes Faxon, p. 71. Ortmann, p. 120. 



This is the common burrowing form of the eastern United States. Hagen 

 records it from Lakes Erie and Ontario and Faxon from Detroit. It has not 

 yet been found within our borders but probably occurs. 



Length up to 111 mm. (Faxon).* Rostrum without lateral spines, areola 

 obliterated in the middle, first abdominal appendages of male hooked, movable 

 finger of large chelae without excavation at base. 



Cambarus inmiunis Hagen. Fig. 8, d. 



Hagen, p. 71; Faxon, p. 99. Ortmann, p. 113. 



This species is reported by Faxon as being found concealed among weeds in 

 muddy pools and ditches connected with the Detroit River. Localities: — 

 Twenty-mile creek near Tintern, Lincoln County. 



Length up to 3*2 inches. Rostrum usually without lateral spines. Areola 

 narrow. Movable finger of large chelae usually excised near base on outer 

 side. First abdominal appendages of male styliform and curved. 



*124 mm. (Williamson). 



