84 ASTACID^. 



terms obtusis ; lamina media parte utrinque bispina, parte apicali, sub- 

 loiigioi'i, elliptica. Pedibus anticis brevibus, latis; chela lata plana, 

 ciliato-jDunctata ; subtus ItBvi, ad marginem internum sulcata ; margine 

 interno 1)revi, incurvo, tuberculoso-serrato ; digitis duplo longioribus, 

 latis, rectis, bicostatis, lineato-punctatis, ciliatis ; digito mobili extus et 

 basi intus tuberculato ; digito externo basi intus tuberculato, extus mar- 

 ginato, punctate. Carpo lato, oblique truncato, parce pimctato, intus 

 subtuberculoso, spina interna media valida, interdum alia basali pai'va ; 

 subtus spinis duabus obtusis anticis, tertia minori interna. Bracliio 

 brevi, la3vi, spinis duabus anteapicalibus oblique positis, subtus spinis 

 biseriatis acutis. Pedibus tertiis articulo tertio unguiculato ; quartis 

 capitulo basali, ovoideo, quintis subnullo. Pedibus abdominalibus bre- 

 vibus, validis, contortis ; intus latis, planis ; extus medio crassioribus ; 

 parte interna breviori, cylindrica, apice inflexa, conica, acumine parvo, 

 compre.sso ; parte externa dente longo apicali subito incurvo, extus 

 fusco-corneo, sti'iato. 



Forma II. difFert chela plerumque lajviori ; pedibus abdominalibus 

 basi articulatis ; parte interna apice obtusiori ; jjarte externa dente 

 apicali latiori, vix separato, breviori, obtuso, extus nee fusco-corneo nee 

 striato. 



Marem vidi magnum pedibus abdominalibus similibus sed basi non 

 articulatis ; chelis magnis, lasvioribus, digitis angustioribus. 



Femina difFert abdomine latiori, basi angustato ; ventre inter pedes 

 quartos nudo ; annulo transverso, modice crasso, lumine denticulato pos- 

 teriori, sulco anteriori longitudinali. 



(Maxim.) Long. corp. 2.9; anteun. 2.5; ped. antic. 2.3. 



Habitat : Athens, Georgia ; South Carolina. 



Vidi specimina multa et juniora. 



Juniores lajviores, acumine variabili, rostro interdum longiori. 



I have examined a female type in the Mus. Acad. Philad. of C. luti- 

 mamis LeConte. It is the largest seen by me, and has the dimensions 

 given by Mr. LeConte, long. corp. 3.3. 



Cat. No. 236, Athens, Ga., Dr. J. LeConte. Male. Fem. Spec. 12.* 



Cat. No. 1849, Milledgeville, Ga. Male. Spec. 1. 



Dry Spec., South Carolina, Mr. L. R. Gibbes. Male. Spec. 1 ; la- 

 belled A. Burtonii Gibbes. 



29. Cambarus Mexicanus Erichson. 



Cambarus Mexicanus Erichson, Wiegmann's Arcliiv, No. 20, T. 12 p 99. 



" Chelis granulatis, gracilibus, subcylindricis, carpis muticis, rostro 

 lato, apice obtusiusculo." 



'* Thorax somewhat compressed, always densely punctulated ; cretas 

 prominent, divergent behind ; rostrum nearly flat, broad, obtuse at the 



