ASTACUS. 143 
Astacus pallipes, LERERouLLET, Mém. Soc. Sci. Nat. Strasbourg, V. 7 (separate pagination), Pl. II., IIT. 
figs, 83-3.4, 1858. 
Astacus pallipes, var. flavus, LEREBOULLET, Mém. Soc. Sci. Nat. Strasbourg, V. 9, 1858. 
Astacus torrentium (Steinkrebs) (in part), Gerstrenpt, Mém. Acad. Impér. Sei. St. Pétersbourg, IX. 577, 
1859. 
Astacus savatilis, Gruse, Hin Ausflug nach Triest und dem Quarnero, p. 73, 1861. 
Astacus saxatilis, Wetter, Die Crustaceen des siidlichen Europa, p. 217, Taf. VII. figs. 3, 5, 1863. 
Astacus fontinalis (Véerevisse a pieds blancs), Carnonnter, L’Ecrevisse, p. 8, 1869. 
Potamobius astacus, G. B. Sownrsy, Continuation of Leach’s Malacostraca Podophthalma Britannie, Nos. 
XVIII., XIX., Tab. XXXIV. fig, 1, 1875. 
Astacus fluviatilis, Woxuny,* The Crayfish, passim, and p. 230 in particular, Frontispiece and figs. 1-60, 
1880. 
Astacus torrentium, Huxtry,* op. cit., p. 296, fig. 61, a, p, G, fig. 62, a, p, 1880. 
Astacus pallipes (der Dollenkrebs), Kiunzineer, Jahresh. Vereins vaterland. Naturkunde Wirttemberg, 
XXXVIII. Jahre., p. 341, 1882. 
Astacus pallipes, Waxon, Proc. Amer. Acad. Arts and Sei., XX. 154, 1884. 
Under the name “Steinkrebs” the older authors appear to have con- 
founded A. torrentium and A. pallipes. They were first separated as distinct 
species in 1858 by Lereboullet with the names A. longicoriis and A. pallipes. 
Gerstfeldt (1859) seems to have had very little material from without the 
bounds of the Russian Empire. Of the “Steinkrebs” he had seen only five 
ill-preserved dried examples from the Rhone, which, as appears from his 
description of them (p. 577), belong to A. padlipes. He considers them to be 
the same species as that described by Schrank and Koch, i. e. A. torventinm. 
Compared with A. torrentium, A. pallipes has a narrower rostrum with a 
longer and narrower acumen; the median keel is more evident, especially 
near the tip of the rostrum; the antenn are shorter, and the peduncle of 
the antennx overreaches the tip of the rostrum by only a small fraction 
of the length of the terminal segment, while in A. dorrenfium it surpasses the 
rostrum by the whole length of the terminal segment; the longitudinal ridge 
on the lower face of the antennal scale is not toothed, as in A. forrentium ; 
behind the cervical suture are several lateral spines; the chelx are more 
coarsely and sparsely tuberculate. For a detailed comparison of these two 
species, see Klunzinger, op. cit. 4 
A. pallipes and A. torrentivm have a rudimentary pleurobranchia on each 
side of the penultimate and antepenultimate somites. In all the other 
species of Astacus which I have examined there is a third pair on the preced- 
ing somite. The first abdominal appendages of the male A. pallipes are 
figured by Brocchi, Ann. Sci. Nat., 6° Sér., Zool. et Paléontol., Tom. II., PE 
XIII. figs. 12, 13 (“Astacus fluviatilis” from Vaucluse). They agree in form 
* Huxley leaves the question of the specific or the varietal value of the forms 4. zodilis and 4 forren- 
tium (= A. fluviatilis and A. pallipes) undecided. 
