HISTOEY OF THE AMERICAN ASTACIM. 



1708. The first North American species made known Avas described 

 by Fabricius, in his Supplementum ErdomobguB Systematica?. It was 

 called Astacus Bariomi, and communicated by Professor Smith Barton. 

 The description is very short, and the locality not given, but it is prob- 

 ably the species more recently determined as A Bariomi by American 

 naturalists. Bosc, Hist, Nat. des Crust,, Suites a Buftbn an x. (1802), 

 describes in few words, repeated by Latreille, Hist, Nat, des Crust,, VI. 

 240. Astacus Bartonii, which he collected in America, The figure given 

 by him is very bad, and it is impossible to identify his species. 



1817. Rafinesque, in the American Monthly Magazine, II. 42, Novem- 

 ber, describes four species, — Astacus limosas, fossor, eiliaris, and pusillus. 

 His descriptions are likewise very short, but the locality is given, 

 and it will therefore be possible to determine them exactly by further 

 investigations. 



.1. Mmosas is perhaps A affinis Say, and A. fossor the species de- 

 scribed by me as A. obscurus, if it has burrowing habits. A. eiliaris is 

 apparently .1. Bariomi, but the dimensions given by Rafinesque are, as 

 for the foregoing species, excessive. The ciliated legs do not belong 

 exclusively to this species. I think A. pusillus does not differ from A. 

 ciMaris. The differences given are not important, — "the rostrum oval 

 acute," " the hands oblong, dotted," " entirely fulvous brown " ; in A. 

 ciMaris, "the rostrum short, acute," " the hands short, thick dotted," 

 " entirely olivaceous brown." Perhaps A. pusillus is the second form of 

 the male ; still, ciliaa always occur on its second pair of legs, and Rafi- 

 nesque would have mentioned the fact in this instance no less than in 

 A. ciMaris. 



One month after the appearance of the account of Rafinesque, Th. 

 Say, in Journ. Acad. Phil., I. Part I. 167, December, described two 

 species, — A. Bartonii and affinis. His descriptions are good, and suf- 

 ficient to designate the species. A supplement is given, 1. c. 443, con- 

 cerning the variation of their armature and the proportion of the 

 hands in A. Bartonii ; but here perhaps Mr. Say speaks of a different 

 species. Astacus Bartonii Say is probably the species described by 

 Fabricius, and Astacus affinis seems to be Astacus Umosus Rafinesque. 



