CAMBAEUS. 121 



Length of chela. 16 mm. Breadth of chela, 7.5 mm. Length of movable 



finger, 10.5 mm. 



The largest female specimen is CD millimeters in length. 



Locality.— Cypress Creek, Lauderdale Co., Ala. 



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

 by C. L. Uerrick for the U. S. National Museum, October, 1882. 



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 linger on the inner side. 



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

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

 ble those obtained by Mr. Uerrick in Alabama, and belong, 1 think, to the 

 same species. The external linger 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. Montezumse.) 



Third segment of the second and third pairs of legs hooked. First pair 

 of abdominal appendages of the male similar to those of the species included in 

 Group IV. 



51. Cambarus Montezumas. 



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



Camtaru, Montezum*, Sattssuke, Rev. ,, Ma S . de ZooL, * Ser., IX. 101 L857.-Mem. Soc. Pbys.Hist. 



Nat Geneve,XIV 159, PI. III. fig. 22, 1858. T ___ .. . .,„ |fi .„ 



Cambaru* Wontezum*, rar. Mdm, Vo* Martens, .U,l, Naturgesch., WW DI. Jahrg.,1. 130, 1872. 



u Montezuma, Faxon, Proc. A.mer. load. Arts and Sci., W. L49, L884. 



Cambarus Mordesumce and C. Shufeldlii are small species distinguished from 

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

 and third pairs of legs of the male. In 0. Montezuma 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 Saussure, its mar- 

 gins are subparallel from the base to aear the extremity, where the} con- 



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