CAMBAHUS. |-jl 



Length of chela, 10 mm. Breadth of chela, 7 "> nun. Length of movable 

 finger, 10.5 nun. 



The largest female specimen is 00 millimeters in length. 



Locality. Cypress Creek, Lauderdale Co., Ala. 



Nine specimens, four males of the lirst form and five females, collected 

 by C. L. Herrick for the U. S. National Museum, October. 1XS 



This is a small species with large hand, slender lingers widely separated 

 at base and meeting only at the tips. In the female there is a heavy beard 

 at base of external finger on the inner side. 



In the summer of 1872, I collected in a brook at Knoxvillc, Tenn., six 

 specimens, three second-form males and three females, which closely resem- 

 ble those obtained by Mr. Herrick in Alabama, and belong, I think, to the 

 same species. The external finger of the males is densely bearded within at 

 the base, as in the females from Alabama; the first abdominal appendages 

 reach forward to the base of the second pair of legs, are bifid at the tip, the 

 internal and external parts are thick, blunt at the tip, the outer somewhat 

 longer than the inner, and slightly recurved at the tip. 



GROUP V. (TYPE, C. Montezumee.) 



Third segment of the second and third pairs of leg* hooked. Firxl /></!, 

 of (tMoiniiii.il appendages of the male similar to those of the sjiccies included in 

 Group IV. 



51. Cambarus Montezumae. 



Plate II. fig. 6, Plate X. tigs. 7, 7', 7 a, 7 a'. 



Cambafits ~tf<jnle:u>,i/r, SAUSSURE, Rev. et M:iir. do Zool, 2" Ser., IX. 102, 1S57. Mem. Soc. Pliys. Hist. 



Nat. Geneve, XIV. 459, PI. III. fig. 22. 1858. 



Cambarus Monh-:it,iur, var. tr'xleitx, VON MAKTKXS, Arch. Xatunjrsrli., XXXVIII. Jaliri,'., I. 130, 1872. 

 Cambarus 3Ionte:umte, FAXON, Proc. Amcr. Acuil. Arts and Sri., XX. Mil, 



Cambarus Monleztomr and C. ShxfMIH are small species distinguished from 

 all the others of the genus by having hooks on the third joint of tli 

 and third pairs of legs of the male. In C. 31trzuii/<r the rostrum is plane or 

 lightly concave above, with a slightly raised margin; it varies much in its 

 shape. In the typical form, as described and figured by Saussnre. its mar- 

 gins are subparallel from the base to near the extremity, where they con- 



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