138 A REVISION OF THE ASTACID.E. 



vision by Erichson.* Of the described European species, A. aiiffidosits Ratlike, 

 A. pachypuH Rathke, and A. Caspius Eichwald, were known to Erichson only 

 through the previous descriptions. He suggests that A. Caspius may prove 

 to be the same as A. pachi/pus, a surmise that was afterwards shown by Gerst- 

 feldt to be just. Erichson had the opportunity to examine Koch's typos 

 of A. iorrenlimn, saxutiUs, and /rislis, and notes their clear specific separation 

 from A. fluviatilis, and their close affinity with each other. lie shows that 

 the dark color of il. trislls is due to a coating of adhesive mould, and dis- 

 misses the question of the specific value of the differences with the remark 

 that the distinctions may have been more evident in living specimens. 



In 1859 the European Astaci were subjected to a second revision at the 

 hands of Gerstfeldt.f The material at Gerstfeldt's command was rich in speci- 

 mens from Russia, but poor in examples from Central and Western Europe. 

 Gerstfeldt i-eaches the conclusion, that all the described European species of 

 Astacns may be reduced to two valid species, A. J/iiviafiiis and A. lor/rutitiiu 

 (Steinkrebs). He justly points out the identity of A. pac/i//pus Ratlike and 

 A. Caspius Eichwald, and further claims that A. kpfodacfz/lus Eschscholtz, 

 A. anffulosus Rathke, and A. pach^pus Rathke, are but varieties of A. Jluiin- 

 tilis, resultino; from conditions of climate and of the water inhabited bv 

 the several forms. Of the so-called Steinkrebse of the central and western 

 parts of Europe, Gerstfeldt appears to have had but five specimens, all from 

 the Rhone. These he regards the same with Cancer torraitium Schrank, 

 A. saxatilis Koch, A. iristis Koch, and A. hiit/icornis Lereboullet. In reality 

 Gerstfeldt's Steinkrebse belonged to the species described and figured the 

 previous year (in a memoir unknown to Gerstfeldt) by Lereboullet,t under 

 the name A. jtallipes (Dohlenkrebs), a distinct form from Cancer torreniium 

 Schrank (=: A. saxatilis, trisiis, and iorrentimn of Koch, A. longicornis of Lere- 

 boullet). 



In 1869 Heller § described five species from Southern Europe; viz. A.flu- 

 viaUlis Rondelet, A. leptodactjjlus Eschscholtz, A. anguhsus Rathke, A. pach>/pus 

 Rathke, and "4. saxatilis Koch." As synonymes of A. saxatilis, Heller in- 

 cludes A. saxatilis Koch, A. tristis Koch, A. torrentium Schrank et Koch, and 

 A. fluviatilis Bell. Heller's A. saxatilis is the species described by Lereboullet 



* UubersicUt der Artcii dcr Gattung Astaciis. Arcli. Naturgescli., XII. Jahrg., pp. 80-103, ISKj. 



t Ufbcr dio Fhisskrelisc Eiiropa's. Mem. Acad. Impur. Sci. St. Petersbourg, IX. 519-589, 1859. 



X Description de deux uouvelles Espcoes d'.fiorevisses de nos Rivitivs. Mem. Soc. Sci. Nat. Stras- 

 bourg, Tom. v., 1858, 11 pp. 3 pi. 



§ Die Crustaoeen des siidliclien Europa. Crustacea Pudoplitbaliiila, pp. ^12-218, Taf. VII. figs. 3-6, 

 1863. 



