CAMBARUS. 33 



10. Cambarus spiculifer. 



Plate II. «(,'• r>. 



dttaetu spiculifer, Le Contk, Proe. Acad. Nat. Sci. Phila., VII. 401, 1855. 



Cambarus spiculifer, Hagek, 111. Cat. Mus. Comp. Zool., No. 111. p. 48, PL I. figs. 59-62, PI. III. fig. 147, 



L870 

 Cambarus spiculifer, Faxon, Proc. Amer. Acad. Arts and Sci., XX. 13S, 1884. 



Known Localities. — Upper Georgia : Oconee River at Athens and Milledge- 

 ville ; Ocmulgee River in the neighborhood of Atlanta (Coll. Butler Univ., 

 from D. S. Jordan) ; Chattahoochee River at Roswell, Cobb Co., and near 

 Gainesville; Etowah River (Coll. Butler Univ., from I). S. Jordan). 



There is a male type, form I., in the Museum of Comparative Zoology, 

 and one in the Academy of Natural Sciences of Philadelphia. 



In none of the specimens seen by me are there three spines on each 

 side of the basal segment of the telson, as is said by Hagen to be some- 

 times the case (p. 49), nor have I seen an individual with but one lateral 

 thoracic spine (Hagen, p. 50). I think these statements are based upon 

 erroneous determinations, for in the jarful of specimens from Athens, Ga,, 

 labelled Cambarus spiculifer by Hagen, I find the young of C. Lecontei, which 

 has a trispinous telson and one lateral thoracic spine. 



Measurements of a male, form II. — Length, 71.5 mm. Carapace, 34.5 mm. 

 Abdomen, 37.5 mm. From tip of rostrum to cervical groove, 25.5 mm. ; from 

 cervical groove to posterior margin of carapace, 9 mm. Length of rostrum, 

 11.25 mm. ; breadth of rostrum at base, 5.5 mm. ; between lateral spines. 

 2.75 mm. Length of chela, 29 mm. ; breadth of do., 11 mm. Width of areola, 

 3.5 mm. The largest specimen seen by me is 97 mm. long, male form II. 



Cambarus spiculifer has been found as yet only in Upper Georgia, in the 

 Altamaha and Chattahoochee River basins. 



C. Lecontei, C. angustaius, C. pubescens, C. spiculifer, and C. versuius are dis- 

 tinguished from the other species of Group I. by the shortness of the 

 cardiac region of the carapace. C. Lecontei, C. angustaius, and C. pubescens 

 have one lateral thoracic spine on each side; C. spiculifer and ('. m-xii/it* 

 have two. C. Lecontei and C. angustaius have subcylindrical hands, areola 

 of moderate width, rostrum smooth and hollowed out above; C. pubescens 

 lias broader hands mid areola, rostrum pubescenl and subplane above. In 

 C. angustaius the sides of the rostrum are subparallel ; in ('. Lecontei the 

 rostrum is more tapering. In both C. spicuUfer and ('. versutus the areola is 



