145) 



the year their presence is known only by the chimneys which they raise 

 over the mouth of the holes. 



Cambarus immunis Hagen. This species is exceedingly abundant dur- 

 ing the summer in muddy ponds. They burrow into the mud on the dry- 

 ing up of the ponds. T have never observed them in running water. 



Cambarus pellucidus Tellkampf. The common blind crayfish occurs in 

 many of the caves of southern Indiana. They are usually small, the larg- 

 est I have ever seen, among 40 specimens, being barely 2 inches in length. 

 They are kept from extinction only by the inacessibility of their home. 

 They are very conspicuous when in the water, and are very easily caught. 

 When startled they are utterly at loss where to go, and often dart out upon 

 the shore. I think it may be safely said that as a rule they grow spinier as 

 one advances southward, although there are exceptions. A female col- 

 lected in Wyandotte Cave is almost without spines ; but three specimens 

 from a small cave near there are exceedingly spiny. 



Cambarus pellucidus var. trstii Hay. This crayfish, although at first 

 thought to be a distinct species, is probably only a variety of the preceding, 

 characterized Ijy the entire absence of spines. There are no teeth on the 

 rostrum or spines on the sides of the carapace, things never lacking in the 

 common species. The type specimens, 12 or 13 in number, were collected 

 in Mayfield's cave, near Bloomington. They have since been received from 

 Truett's cave, in the same county. 



Cambarus propinquus Girard. This is apparently the common species 

 throughout the state. In the central portion it is very abundant at all sea- 

 sons of the year, being almost invariably found in running water. The 

 median carina on the rostrum, one of the characteristic marks of the spe- 

 cies, may vary from a long ridge to a mere papilla-like elevation. The 

 color in life is a dingy dark olive. The tips of the cheLc are sometimes 

 red, and the spines on the rostrum brown. 



Cambarus putnami Faxon. In his " Monograph on the American Asta- 

 cidjB," Dr. Faxon mentions the probability of this species occurring in the 

 southern part of the state. I have specimens taken between Paoli and 

 Wyandotte cave, in the summer of ISSS. 



Cambarus rusiicus Girard. This species, which is very like propinquus, 

 is tolerably common. It has been collected at Madison and at Indianapolis. 



Cambarus sloanii Faxon. The only known locality for this species in 

 Indiana is in the region about New Albany. 



