CRAYFISHES. 383 



to cervical groove, 22 mm.; length of chela, 35 mm.; Iireadth of chela, 15 mm.; 

 length of dactylus, 21.5 mm. 



Huntsville, Madison Co., Alabama. One male, form I. M. C. Z., No. 301. 



This specimen was considered to be C. immunis by Hagen, is mentioned 

 1)}' him on page 72 of his Monograph, and its chela is probably the one figured 

 by him on PI. VIII, fig. b. Compare my "Revision of the Astacidae," p. 100. 



Six specimens in the U. S. National Museum, three of which are males of the 

 second form, and three females (No. 23,092) collected by Mr. J. E. Benedict at 

 Nashville, Tennessee, in May, 1897, without much doubt are conspecific with 

 the type specimen of C. validus. As they are younger than the type specimen, 

 and as the first form of the male is not represented among them, the peculiarities 

 of the species are not so well pronounced. The chelae are proportionally smaller 

 and the curve of the immobile finger is less. This finger, as in the type specimen 

 and in C. wimunis, is hea\-ily Ijearded within at the base. The gonopodsof the 

 males are similar to those of second-form males of C. immunis, but less strongly 

 curved; indeed the curve of the stem of the organ is no greater than it is in C. 

 virilis, but the ])limt reciu-\'ed tips are subequal as in C. immunis; in other words 

 the shape of the second form male organ is the same as in C. alabamensis. The 

 annulus ventralis of the female is virtually the same as in C. immunis. 



Cambarus mississippiensis Faxon. 



New locality: — Agricultural College, Oktibbeha Co., Mississippi (U. S. 



N. M.). 



Cambarus lancifer Hagen. 



A female specimen, collected by Robert Kennicott at Cairo, 111., is in the 

 U. S. National Museum. The few specimens heretofore known have come from 

 Root Pond, jVIiss., Vicksburg, Miss., and the St. Francis Ri\-er at Greenway and 

 Big Bay, Clay Co., Ark. 



Cambarus bartonii (Fabricius). 



New localities: — Maine: Little Madawoska River, a tributary of Aroostook 

 River at New Sweden, Aroostook Co. (M. C. Z.); brook tributary to 

 Ai-oostook River at Caribou, Ar-oostook Co. (Coll. W. P. Hay). New York: 

 Schoharie Creek, Catskill Mts., Green Co. alt. 2,000 ft. (U. S. N. M.); Little 



