646 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xx. 



are truncate at the tip, the outer part terminating in two small recurved 

 teeth, the inner part in a slender spine which is directed outward. 



Gum Cave, Citrus County, Florida (Coll.U.S. IsT.M.). Two females, 

 twelve young (male, Form II; female). 



Lonnberg's types of Gamharus acherontis, two males, 50 and 55 mm. 

 long, were procured in sinking a well, from a subterranean rivulet 

 about forty-two feet from the surface, in Orange County, Florida. 

 According to Lonnberg's description and figures, the chela is thicker 

 than in the Citrus County examples above described, the telson is 

 shorter, the abdominal pleura? more acuminate, and the antennal scales 

 more triangular in form. Following the description alone, the rostral 

 acumen is blunt and its base extends back into the rostral groove as a 

 slight ridge. These conditions are not true of the Citrus County speci- 

 mens, neither are they shown in Lonnberg's figures of G. acherontis. 

 The only adult examples in the Citrus County lot, moreover, are 

 females, while Lonnberg's specimens were both males. I am therefore 

 inclined to believe that the discrepancies between the Swedish author's 

 account of G. acherontis and the specimens before me are due to dif- 

 ferences in age and sex, and in part to inaccuracy of description and 

 delineation. 



This species, the fourth blind Gambarus described from the United 

 States, is very distinct from any of the others. As pointed out by 

 Lonnberg, it is probably descended from C. clarMi. It is noteworthy 

 that in a specimen of G. clarMi collected in St. Johns Eiver, Florida, 

 the areola, although narrow, is not obliterated in the middle. In this 

 respect this specimen agrees with G. acherontis as well as with Texan 

 specimens of G. clarMi, and differs from the form of G. clarMi found in 

 Alabama, Mississippi, and Louisiana. That the maximum age of the 

 caverns in which G. acherontis lives is probably Post-pliocene has been 

 shown by Lonnberg. 1 



CAMBARUS PUBESCENS Faxon. 



Buckhead Creek, Millen, Burke County, Georgia (Coll.U.S.N.M.). 



CAMBARUS VERSUTUS Hagen. 



Pollard (Escambia County), Greenville (Butler County), and Calera 

 (Shelby County), Alabama (Coll. U.S.N.M.).. All of these specimens 

 have a carinated rostrum. 2 



CAMBARUS ALLENI Faxon. 



This species is recorded by Lonnberg 3 from Apopka (Orange County), 

 Arcadia (DeSoto County), and from Hillsboro County, Florida. 



Bihang till K. Svenska Vet.-Akad. Handl., XX, Pt. 4, pp. 8, 9, '1894. 

 ! Rev. Astacidas, p. 34, and Proc. U. S. Nat. Mus., XII, p. 619. 

 ; Bihang till K. Svenska Vet.-Akad. Handl., XX, Pt. 4, p. 1, 1894. 



