180 Wisconsin Academy of Sciences^ Arts, and Letters. 



II. — Dorsal areola none. C. obesus. 



Cambarus acutus (Girard) has been found in Racine county by 

 Dr. Hoy. It occurs also in marsh ditches near Sauk City in com- 

 pany with C. obesus. 



a stygius (Bundy). Bulletin No. 1, 111. Mus. Nat. Hist., 1876. 



A number of small crawfish were sent me by Dr. P. R. Hoy, 

 by whom they were found on the shore of Lake Michigan at 

 Racine, having been washed ashore during a storm. Proving to 

 be a new species, they were described under the above name. 

 The rostrum is long and pointed, smooth above, foveolate at base; 

 cephalothorax slightly compressed, smooth or slightly punctate 

 above and finely granulate on sides. The dorsal area is narrow 

 and the lateral spines acute, antennal plates wide, truncate, with, 

 short apical teeth ; epistoma rounded in front, twice as wide as 

 long ; third maxillipedes hairy on inner and lower sides ; hands 

 short, smooth, serrate on inner margins, fingers short, nearly 

 straight, ribbed and punctate above, with contiguous margins tu- 

 berculate, outer one hairy; third segment of third (and probably 

 fourth) thoracic legs of male hooked. (The specimens were so 

 badly mutilated during the transfer through the mail that I could 

 not determine this point, not one of the three males sent me hav- 

 ing the fourth legs remaining.) The first abdominal legs of male 

 are short, truncate, with three short obtuse teeth directed out- 

 ward from posterior margins of apex, leaving a smooth groove 

 passing up on outer surface between these teeth and the anterior 

 margin. The ventral ring of female is flat, transversely elliptical, 

 with posterior margin slightly elevated. This species resembles 

 C. acutus, but can be instantly separated by the short hands and 

 non-tuberculate annulus of female. The color of these speci- 

 mens when cauiht was a dark cream, darker along sutures. In 

 alcohol they changed to a purplish black, not confined to the 

 exoskeleton, but extending to the adjacent soft tissues. 



C. viriles (Hagen) is our most abundant species. It will doubt- 

 less be found in all the streams of the state. 



A male in my collection, taken on a fisherman's net at Jeflfer- 

 SOD, belongs to Hagen's variety A. It is the largest crawfish I 

 have seen, measuring 6|- inches from tip of telson to that of ros- 



