CAMBAE1 S 



GROUP III. (Type, C. Bartonii.) 



59 



Third segment of third pair of legs hooked. Firs! pair of abdominal appen- 

 dages of the male thick, the inner and meter parts each terminating in a short 

 recurved tooth. 



The more typical forms of this group have no lateral teeth on the ros- 

 trum, but in 0. extrancus, Jordani, Girardianus, cornutus, and hamuktus, lat- 

 eral rostral teeth are present, Of these five, only C. exlraneus was known 

 to Dr. Hagen, who placed it, on account of the rostral teeth, as an aber- 

 rant species in the C. affinis group. I think the structure of the male ap- 

 pendages is of much greater value in determining the subordinate groups 

 of Cambarus than the form of the rostrum, which presents every condition 

 between one with well-developed lateral teeth and one with entire margins. 

 C. cornutus is peculiar in the enormous development of the antennal flagella. 

 ('. hamulaius, like C. pellucidus in Group L, is blind. It has slender chelae, and 

 resembles C. pellucidus a good deal in its general form. 



Rostrum without 

 lateral teeth. 



Areola broad. Rostrum long, tapering C. acuminates. 



Areola of moderate width . . . C. Bartonii, C. ktimanus. 



Areola narrow "■ duoius. 



Rostrum excavated above . C. Diogenes, C.argillicola. 



Rostrum plane above . . C. Uhleri. 



. Incertse sedis .... C. Nebrascensis. 



w Areola obliterated in the middle. 



[Antennse of normal size. C. Girardianus, G. Jordani, C. extraneus. 

 Rosi rum with J Eyes well developed, j ^^^ wjth , arge flageU m Ilj c iliate on inner side. C. cornutus. 

 lateral teeth. \ Eyes rudimentary C. hamulatus. 



22. Cambarus Bartonii. 



P Astacus Bartonii, Fabeicius, Ruppl. Bntomolog. Systemat., p. 107, 1708. 



? Astacus Bartonii, Bosc, Histoire NatureUe des Crustacfo, II. 62, PI. XL fig. 1, 1S02. (2d ed., IT. 10, 



I 'I. \l li-. 1, is:i0.) 

 p Jstacus Bartonii, Lateetlle, Bist. Nat. Gdn. el Partie. des Crustace's el des Insectes, VI. 240, 1803 



( Vl'ier Fabricius.) 

 Astacus ciliaris, Rafinesque, A.mer. Monthly Mag. and Crit. Rev., II- I:-'. Nov. 1817. 

 P Astacus pusittus, Hmim.mii b, i.mer. Monthlj Slag, and Crit. Rev., 11. 1-', Nov. 1817 

 Astacus Bartonii, Sat, Jour. lead. Nat. Sci. Phila., I. 167, Dec. L817. 



P Astacus Bartonii, Desmabest, Consid Cm. sur la Classe des Crustacfo, p. 212,1825. (After Fabricius.) 

 Astacus Bartonii, Eablak, Med. and Phys. Researches, p. 230, fig. •% 1S35. 

 Astacus affinis, Milke Edw lbds, IIi-i Nat. Crusi . II. W2, 1837. 

 Astacus Bartonii, Goi ld, Rep. [nvert. Mass., |>- 330, 1841. 



Utacus Bartonii, Thompson, Bist. Ver , I'm I. p. L70, 1842. (With a worthless cut.) 



Astacus Bartonii, De Kay, Zoologj of New Xork, Pari VI . Crustacea, p. 22, PI. VIII. fig. 25, L844. 

 Cambarus Bartonii, Gikakh, Proc. Acad. Nat. Sci. Phila., VI 88, L852 (No description.) 



