10 A REVISION OF THE AST ACT RK. 



flattened hands, belongs alone, then, to Saussure's C. Aztecus. In the second 

 form the antenna] scale is more broadly truncate at the end, and the ros- 

 trum is a little different. These differences are not striking enough, however, 

 to preclude the specific identity of the two forms. 



Of the species of Cambarus described by American authors before the 

 date of Hagen's Monograph, but few types are extant. The oldest known 

 to me are Harlan's, 1830, 1835 (A. Blandingii Har., A. Bartonii Fab., A. affinis 

 Say), preserved in the collection of the Academy of Natural Sciences of 

 Philadelphia. 



In 1850, Professor Lewis R. Gibbes enumerated, without describing, four 

 species of Cambarus under the names Astactis Bartonii Fab., A. affirds Say, 

 A. Blandingii Harlan, and A. pellucidus Tellk. Several specimens labelled by 

 Gibbes in the collection of the Philadelphia Academy and in the Museum 

 of Comparative Zoology prove that his identifications were often incorrect, 

 and consequently the localities given by him cannot be taken as authori- 

 tative. Under the name of A. Bartonii Gibbes appears to have confounded 

 three distinct species: C. Bartonii (Fab.), C. latimanus LeC, and C. rusticus 

 Gir. (See p. 65.) The localities South Carolina and Alabama cited by 

 Gibbes under A. Bartonii probably refer to C. latimanus. Gibbes's A. affinis 

 is the true A. affinis of Say, as is shown by a specimen in the Philadelphia 

 Academy's collection ; but the locality, "Florida," attributed to this species 

 in Gibbes's paper, undoubtedly belongs to some other species. A specimen 

 in the Museum of Comparative Zoology, determined as A. Blandingii by 

 Gibbes, is O. troglodytes (LeC); and to this species Gibbes's habitat, ''the 

 low country of South Carolina," properly appertains 



Girard in his Revision of the North American Astacida^ (Proc. Acad. Nat. 

 Sci. Phila., 1852) enumerates twenty species of Cambarus, twelve of which 

 are new. The diagnoses are in many cases insufficient for the identification 

 of the species, and it therefore becomes highly important to fix the spe- 

 cies through an examination of typical specimens. Two of the species in 

 Girard's list. C. fossor (Raf.) and C. Oreganus (Randall), were unknown to 

 Girard, and remain doubtful to the present day. 0. Gambelii (types in the 

 Philadelphia Academy) is an Astacus. The types of most of Girard's species 

 were formerly in the collection of the Smithsonian Institution at Washing- 

 ton, whence they were transported by Dr. Stimpson to the Chicago Academy 

 of Science, and there consumed in (lie great lire of 1871. Fortunately, 

 before their destruction types of five of the eleven new Cainhan and two 



