138 A REVISION OF THE ASTACIDA. 
9) 
vision by Erichson.* Of the described European species, A. angulosus Rathke, 
A. pachypus Rathke, and A, Caspius Kichwald, were known to Erichson only 
through the previous descriptions. He suggests that A. Caspius may prove 
to be the same as A. pachypus, a surmise that was afterwards shown by Gerst- 
feldt to be just. Erichson had the opportunity to examine Koch’s types 
of A. torrentium, saxatilis, and tists, and notes their clear specific separation 
from A. fluviatilis, and their close affinity with each other. He shows that 
the dark color of A. ¢ristis 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.t The material at Gerstfeldt’s command was rich in speci- 
mens from Russia, but poor in examples from Central and Western Kurope. 
Gerstfeldt reaches the conclusion, that all the described European species of 
Astacus may be reduced to two Valid species, A. fliviatilis and A. torrentiun 
(Steinkrebs). He justly points out the identity of A. pachypus Rathke and 
A. Caspius Kichwald, and further claims that A. leptodactylus Eschscholtz, 
A. angulosus Rathke, and A. pachypus Rathke, are but varieties of A. fluria- 
tis, resulting from conditions of climate and of the water inhabited by 
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 torrentium Schrank, 
A. saxatilis Koch, A. tristis Koch, and A. longicornis 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. pullipes (Dohlenkrebs), a distinct form from Cancer torrentinn 
Schrank (= A. saxatilis, tristis, and torrentium of Koch, A. longicornis of Lere- 
boullet). 
In 1869 Heller § described five species from Southern Europe ; viz. A. flu- 
vutis Rondelet, A. leptodactylus Eschscholtz, A. angulosus Rathke, A. pachypus 
Rathke, and “A. sazatilis Koch.’ As synonymes of A. saxatilis, Heller in- 
cludes A. sazatilis Koch, A. tristis Koch, A. torrentium Schrank et Koch, and 
A. fluviatilis Bell. Hleller’s A. saralilis is the species described by Lereboullet 
* Uebersicht der Arten der Gattung Astacus. Arch. Naturgesch., XII. Jahrg., pp. 86-103, 1846. 
+ Ueber die Flusskrebse Envopa’s. Mém. Acad. Impér. Sci. St. Pétersbourg, IX. 549-589, 1859. 
{ Description de deux nouvelles Hspeces d’Ecrevisses de nos Rivitres. Mém. Soc. Sci. Nat. Stras- 
bourg, Tom. V., 1858, 11 pp. 3 pl. 
§ Die Crustaceen des siidlichen Europa. Crustacea Podoplthalmia, pp. 212-218, Taf. VII. figs. 3-6, 
1868. 
