T/ialassinnlea and Astacidea. 303 



Panulirus guttatus^ Gray. 



Dr. T. Hale Streets mentions this species amono; those 

 collected bj J. A. M'Ncil upon the Isthmus of Panama, 

 })resumablj from the Pacific coast. 



Panidirus americamis^ Lamarck. 

 Also included in the above-mentioned cataloQ-ue. 



o' 



Panidirus gracilis^ Streets. 



rdiiuUrus gracilis. Streets, Proc. Acad. Nat. Sci. Phil. 1871, 225, pi. xi. 

 tig. 2. 



This form is described by Streets from a specimen 0*9 inch 

 in length, probably a very young individual. 



Astacus Gamleliij Agassiz. 



This very distinct species appears to be peculiar to the 

 central region of North America ; all the specimens I have 

 seen have been collected east of the Sierra Nevada. 



It is easily distinguished from the species inhabiting the 

 rivers flowing into the Pacific, by the pilose areas upon the 

 upper surface of the chelre, and by the simple rostrum. 



Astacus ni'grescens, Stimpson. 

 Astacus ni(/rcscens, Stimpson, Crust. & Echin. P. S. N. A. p. 52. 



This species appears to be found in most of the larger 

 brooks of the central counties of California, such as the 

 Alameda Creek, Alameda Co., Coyote Creek, Santa-Clara 

 Co., and San-Joaquin Slough. 



It is occasionally sold in the markets of San Francisco. 

 Adult specimens exceed 4 inches in length. 



Astacus Idamathensis, Stimpson. 



Astacus klcpnathensis, Stimpson, op. cit. 54. 



This small species, first found in Klamath Lake by Dr. 

 Newberry, has also been taken in the Columbia Piver ; and I 

 have collected several individuals in Eel River, Humboldt 

 Co.j California. 



Astacus Trowbridgu, Stimpson. 



Astacus Trowhridgii, Stimpson, op. cit. 53. 



The terminal spine of the rostrum is less slender than in 

 A. nigrescens] and a single prominent antero-lateral tooth on 



