150 A EEVISION OF THE ASTACID.E. 



commoner Southern species A. pallipes, which has been very generally con- 

 founded with A. fluviatilis. 



The Astaci from the Spanish peninsula are probably A. pallipes, as well 

 as those of England and Ireland.* 



A. fluviatilis is also found in Denmark (Huxley, op. cil., p. 299) and in 

 the Scandinavian peninsula. It appears to have been introduced artificially 

 into the latter, having been scarcely known in Sweden before the time 

 of John III. (1568-92). t From Sweden it has spread into Southeastern 

 Norway.^ 



9. Astacus leptodactylus. 



Astacus leptodaciylus, ESCHSCHOLTZ, Mem. Soc. Imper. Nat. Moscou, VI. 109, Tub. XVIII., 1823. 

 Astacus leptoduftylus, RATHKE, Mem. Acad. Imper. des Sci. St. Petersbourg, III. 359, Tab. IV. figs. 1, 2, 



1837. (Separate, 1S36.) 

 Astacus leptodactylus, var. Crispin, EICHWALD, Bull. Soc. Imper. Nat. Moscou, 1838, p. 148. Fauna Caspio- 



Caucasia, p. 179, Tab. XXXVI. fig. 1, 1841. 

 Aslacus leptorluc/i/lus, var. salintis, NORDMANN, Observations sur la Faune Poutique, in Demidoff's Voyage 



dans la Russie Merid. et la Crimee, Atlas, Crustacea, Tab. I. (No date.) 

 Astacus leptodactylus, ERICHSON, Arch. Naturgesch., XI. Jahrg., I. 90, 1846. 

 Astacus jtitoiatilis, var. leptodactylus, GEKSTFELDT, Mem. Acad. Imper. des Sci. St. Petersbourg, IX. 55S, 



584, 1839. 



Astacus leptudacli/lus, HELLER, Die Cmstacceu des siidlichen Europa, p. 215, Taf. VII. fig. 6, 1863. 

 Astacus leptodactylus, KESSLER, Bull. Soc. Imper. Nat. Moscou, XLVIII. 249 [349], 1874. 

 Astacus leptodactylus, HUXLEY, The Crayfish, p. 303, fig. 75 (after Rathke), 1880. 

 Astacus leptodactylus, FAXON, Proc. Amer. Acad. Arts aud Sci., XX. 157, 1884. 



VAR. angulosa. 



Astacus angulosus, RATHKE, Mem. Acad. Imper. des Sci. St. Petersbourg, HI. 364, Tab. IV. fig. 3, 1S37. 



(Separate, 1836.) 



Astacus aiifftilosus, ERICUSON, Arch. Naturgesch., XI. Jahvg., I. 91, 1846. (After Rathke.) 

 Astacusjlttviatilis, var. angulosus, GERSTFELDT, Mem. Acad. Imper. des Sci. St. Petersbourg, IX. 563, 584, 



1859. 



Astacus angulosus, HELLER, Die Crustaceen des siidlicheu Europa, p. 216, 1863. 



Astacus leptodactylus, var. aiiyulosus, KESSLER, Bull. Soc. Imper. Nat. Moscou, XLVIII. 251 [351], 1874. 

 Astacus leptodactylus, var. aiiyulosa, FAXON, Proc. Araer. Acad. Arts aud Sci., XX. 157, 1SS4. 



Distribution. Astacus leptodactylus has the widest distribution of any of 

 the European species of Astacus. It is found in all the rivers that flow into 

 the Black Sea and the Sea of Azov on the north from the Danube to Mount 

 Caucasus, and in those that empty into the Caspian Sea as far east as the 

 Ural Mountains and the Muchojar Hills in Western Siberia. It descends into 

 the brackish waters of the estuaries of the rivers that empty into the Black 



* See pp. 144, 145. f Limit-, Fauna Suecica, p. 358, 1746. 



+ G. 0. Sars, Hist. Nat. des Crustacea d'Eau douce de Norvege, p. 11, 1867. 

 The text is dated 1840. 



