658 PROCEEDINGS OF THE NATIONAL MUSEUM. 



process of epistoine blunt at the anterior end, the sides convex, the lat- 

 eral angles protuberant. Carpus armed with a large median and a 

 small posterior spine on the inner border; below, the carpus presents 

 a prominent median spine together with a smaller one situated between 

 the latter and the median internal spine. The chela is of moderate 

 size, punctate, doubly serrate on the internal border, fingers armed 

 with blunt teeth along their prehensile edges, the base of the immo- 

 bile fingers commonly beared within; dactylus about twice as long as 

 the inner margin of the palms. Antennal scale broad, broadest beyond 

 the middle, internal margin very convex. 



First pair of abdominal appendages of the male similar to those of 

 G. palmer I. 



Annulus ventralis of the female triangular, central cavity roundish, 

 not elongated transversely, posterior wall much swollen and divided in 

 the middle by an almost straight, longitudinal closed fissure. 



Length 59 mm. ; carapace 29 mm. ; rostrum 7 mm. ; from tip of rostrum 

 to cervical groove 18.5 mm. ; from cervical groove to posterior margin 

 of carapace 10.3 mm. ; cheiiped 40 mm. ; merits 11.5 mm. ; carpus 7 mm. ; 

 chela 22.5 mm. ; dactylus 15 mm. 



Walnut Fork, Piney, Arkansas (Coll. Mus. Comp. Zool., from S. E. 

 Meek.). Twelve males, Form II; fifteen females. 



Fayetteville, Arkansas (Coll. S. E. Meek.). One male, Form 1; seven 

 males, Form II; five females. 



This small species, discovered in northwestern Arkansas by Professor 

 S. E. Meek, appears to be distinct from any hitherto described. In its 

 general appearance it resembles G. rnsticus, bat the areola is much 

 narrower, as in G. virilis, while the male appendages are fashioned like 

 those of G. palmeri. The first pair of abdominal appendages of the 

 female are reduced to the merest rudiments in the shape of a pair of 

 soft papillae springing from the first sternal segment of the abdomen. 



CAMBARUS RUSTICUS Girard. 



Grand Rapids, Wood County, Ohio; Defiance, Defiance County, Ohio; 

 Ottawa, Putnam County, Ohio; McCutchenville, Wyandot County, 

 Ohio; Tiffin, Seneca County, Ohio; Waterloo, Indiana; Moscow, Hick- 

 man County, Kentucky; Saginaw and Tiffin, Michigan; Springfield 

 and Marshfield, Missouri. (Coll. U.S.KM.) Black River, Black Rock, 

 Arkansas; Shell Rock River, Waverley, Iowa; Indian Creek, Marion, 

 Iowa. (Coll. S.E. Meek.) 



CAMBARUS SPINOSUS Bundy. 



Indian Creek, tributary of Powell's River, six miles southeast of Cum- 

 berland Cap, Tennessee; Clinch River at Walker's Ford, eleven miles 

 south west of Tazewell, Tennessee; Courtland, Alabama. (Coll.U.S.N.M.) 



The specimens from Courtland, Alabama, are three females and one 



