366 CRAYFISHES. 



Its range is now known to include the five states, Texas, Arkansas, New Mexico, 

 Oklahoma, and Kansas. 



Cambarus gracilis Bundy. 



New localities: — Illinois: Abingdon, Knox Co. (U.S. N. M.); Oquawka, 

 Henderson Co. (U. S. N. M.). 



Cambarus hagenianus Faxon. 

 Plate 1; Plate 7, Fig. 1, 7. 



Cambarus carolinus Hagen, nee Erichson. 



Cambarus hagenianus Faxon, Proc. Amer. Acad., 1884, 20, p. 14. 



This species has been hitherto known only through the type specimen in the 

 Museum of Comparative Zoology (No. 232), a male of the first form received 

 early in the history of the Museum from Professor Lewis R. Gibbes of Charleston, 

 S. C. The United States National Museum has recently received it in ample 

 numbers from the Agricultural College, Oktibbeha Co., Miss., and also from 

 Muldon, Monroe Co., Miss., and Farmdale, Ala. It is a pest to the cotton 

 growers of these regions, riddling the fields with its burrows, and devouring the 

 young plants; to a less degree it is destructive to young blades of maize or Indian 

 corn.' 



Hagen's Crayfish attains to a length of three inches. It is nearly related 

 to C. gracilis Bundy, replacing that species in more southern localities. In C. 

 gracilis the sides of the rostrum are more nearly parallel; the sub-orbital angle, 

 which is pronounced in C. gracilis, is wanting in C. hagenianus. The branchio- 

 cardiac lines, although contiguous in both C. gracilis and C. hagenianus for a 

 considerable distance, obhterating the areola, are united for less distance in the 

 former than in the latter; the abdomen is much broader in C. gracilis, and the 

 longitudinal rib on the upper side of the inner branch of the last pair of abdominal 

 appendages terminates in a spine which lies some distance from the posterior 

 margin, while in C. hagenianus this rib extends clear to the margin, where the 

 spine projects freely. The gonopods of the first form male are formed after a 

 similar fashion in C. hagenianus, C. gracilis, and C simulans; there are three 

 terminal teeth (one of which is compressed or laminate) in C. gracilis and C. 



' See U. S. Depart. Agric, Rept. Bureau Biol. Surv. for 1911, p. 9; and A. K. Fisher, Crawfish as 

 Crop Destroyers, Yearbook U. S. Depart. Agric. for 1911, 1912, p. 319-324, pi. 22. 



