OBSERVATIONS ON THE ASTACID.53 IN THE UNITED 

 STATES NATIONAL MUSEUM AND IN THE MUSEUM OF 

 COMPAKATIVE ZOOLOGY, WITH DESCRIPTIONS OF NEW 

 SPECIES. 



By Walter Faxon, 



Assistant in chnr<je of Molliisca and Crustacea, Museum of Comparative Zoolofjii, 

 Cambridge, Massachusetts. 



Since tlie publication of my "Notes on North American Crayfishes" 

 in 18!>(», a good deal of material has accumulated in the United States 

 National ^luseum and in the Museum of Comparative Zoology. Tlie 

 flrst i)art of the jiresent article embodies the results of an examination 

 of tliis material.' 



The second part relates to the craytishes of the Southern Hemi- 

 S])here — the Farastachuv. After the publication of Part I of my 

 " Revision of the Astacidiie," which treated of the Northern Ilemi- 

 si)liere genera, Gamhartis and Astacus, I hoped to get togetlier a col- 

 lection of the Parastacine craytishes that would enable me to issue tUe 

 second i)art of the revision in a shape similar to the first part. Disap- 

 pointed in this hope, I have decided to include in this i)aper such results 

 as I could obtain from a study of the Parastacimc in the two museums 

 above named. Thanks to Mr. Charles C. Chilton, of Christchurch, 

 New Zealand, my series of New Zealand crayfishes is ample, but lack 

 of adequate material from Australia, Tasmania, and South America 

 l)recludes a satisfactory revision of the Parastacinw as a whole. 



Six new species and three new subspecies of Camharus are described 

 and figured in this paper. Of these, five belong to the United States, 

 four to Mexico. Five new species of Parastaeiis are also described and 

 figured — two from Uruguay, two from Chile, and one ostensibly from 

 Mexico. 



'Anyone who wmlertakes tbe perploxinj^ study of the North American crayfishes 

 should have at hand the foUowing- works: 1. Monograph of the North American 

 Astacida". By Hermann A. Hagen. 111. Cut. Mns. Comp. Zool., No. 3 [Mem. Mus. 

 Comp. Zool., II, No. 1], 1871. 2. A Revision of tlii^ Astacida*. Parti. The (Jcucra 

 Camharus and Astacus. By Walter Faxon. Mem. Mus. Comp. Zool., X, No. 4, 1S85. 

 3. Notes on North American Crayfishes — Family Astafida". By Walter Faxon. 

 Proc. U. S. Nat. Mus., XII, pp. G19-()34, 1890. 4. The present article. In these 

 works all the North American crayfishes are described and many of them figured. 



PROCEEDINGS U- S- NATIONAL MUSEUM, VOL. XX-NO. 1136. 



643 



