156 MARINE AND FISHERIES 



5 GEORGE v., A, 191& 



A^ First abdominal appendages of male stylif orm and curved (Fig. 8, d) . Rostrum 



without lateral teeth or occasionally with C. immunis. 



A3 First abdominal appendages of male styliform and straight (Fig. 8, a, b, c 

 Rostrum with lateral teeth (Fig. 9, a, b, c). 



Dj Sides of carapace with many teeth (Fig. 9, c) C limosus. 



D2 Sides of carapace with only one distinct tooth on each side (Fig. 9, a, b). 

 Ej Areola of moderate width (Fig. 9, a). First abdominal appendages of 



male with short tips (Fig. 8, a) C. propinquus. 



E2 Areola rather narrow (Fig. 9, b). First abdominal appendages of male 

 with long, tapering tips (Fig. 8, b). 



Fi Sides of rostrum straight C. virilis. 



F2 Sides of rostrum concave C. rusticus. 



Having examined only five of the eight species, I have not been able to devise 

 a key for all the species, that would be applicable to both sexes. The five species 

 can be readUy distinguished from each other by characters of the carapace or 

 chelipeds, as shown in figures 9 and 10. The following keys may be found useful 

 and include all the species* that have been found within our borders but not all 

 that will probably be found to occur. 



W W 



rr\\. 



a 



b 



c d 



Fig. 9. 



e 



f 



Key based upon the characters of the carapace. (Fig. 9). 



Aj Rostrum with lateral teeth. 



Bj Numerous spines on sides of carapace C. limosus. 



Bj Only one pair of spines on sides of carapace. 



Ci Areola broad (about 2 mm) C propinquus. 



C2 Areola narrow (about 1 mm) C. virilis. 



A2 Rostrum without lateral teeth. 



•Except C. immunis. 



