2. _Eryx jaculus_ (Greece, Turkey, Roumania). 3. _Tropidonotus natrix._ 4. _Tropidonotus tessellatus._ 5. _Zamenis gemonensis._ 6. _Zamenis dahlii_ (coast of the Adriatic, Greece). 7. _Coluber quatuorlineatus._ 8. _Coluber longissimus._ 9. _Coluber leopardinus._ 10. _Coronella austriaca._ 11. _Coelopeltis monspessulana_ (West Coast, Greece, and islands). 12. _Tarbophis fallax_ (West Coast, Greece and islands, Constantinople). 13. _Vipera ursinii_ (Bulgaria, Bosnia, Herzegovina, Montenegro). 14. _Vipera berus_ (Bosnia, Herzegovina, Roumania). 15. _Vipera aspis_ (Bosnia). 16. _Vipera ammodytes._ 17. _Vipera lebetina_ (Cyclades). X. RUSSIA 1. _Tropidonotus natrix_ (as far north as 60°). 2. _Tropidonotus tessellatus_ (south). 3. _Zamenis gemonensis_ (south). 4. _Zamenis dahlii_ (Caucasus). 5. _Coluber quatuorlineatus_ (south). 6. _Coluber dione_ (south, between Volga and Ural). 7. _Coluber longissimus_ (south, Poland). 8. _Coluber leopardinus_ (Crimea). 9. _Coronella austriaca_ (as far north as 57°). 10. _Contia modesta_ (Caucasus). 11. _Tarbophis iberus_ (Caucasus). 12. _Vipera renardi_ (south). 13. _Vipera berus_ (as far north as 64°). 14. _Ancistrodon halys_ (south, between Volga and Ural). Without attempting anything like a complete bibliography, we have compiled a list of faunistic works and papers dealing with the snakes of Europe: EUROPE IN GENERAL SCHREIBER, E.: Herpetologia Europæa. Zweite Auflage, Jena, 1912, 8vo. STEINHEIL, F.: Die Europaeischen Schlangen. Kupferdrucktafeln nach Photographien der lebenden Tiere. Jena, 1913, 4to. (in progress). GREAT BRITAIN BELL, T.: A History of British Reptiles. 2nd edit., London, 1849, 8vo. COOK, M. C.: Our Reptiles. London, 1865, 8vo. LEIGHTON, G.: The Life-History of British Serpents. Edinburgh and London, 1901, 8vo. FRANCE GADEAU DE KERVILLE, H.: Faune de la Normandie. IV. Reptiles. Paris, 1897, 8vo. LATASTE, F.: Essai d'une Faune Herpétologique de la Gironde. Bordeaux, 1876, 8vo. MARTIN, R., ET ROLLINAT, R.: Vertébrés sauvages du Département de l'Indre. Paris, 1894, 8vo. SWITZERLAND FATIO, V.: Faune des Vertébrés de la Suisse. III. Reptiles et Batraciens. Geneva and Basle, 1872, 8vo. SPANISH PENINSULA BOSCÁ, E.: Catalogue des Reptiles et Amphibies de la Péninsule Ibérique et des Îles Baléares (Bull. Soc. Zool. France, 1880). ITALY BONAPARTE, C. L.: Iconografia della Fauna Italica. II. Anfibi. Rome, 1832-1841, fol. CAMERANO, L.: Monografia degli Ofidi Italiani (Mem. Acc. Torin., [2] xxxix., 1888, and xli., 1891). GERMANY DÜRIGEN, B.: Deutschlands Amphibien und Reptilien. Magdeburg, 1890-1897, 8vo. LEYDIG, F.: Ueber die Einheimischen Schlangen (Abh. Senck. Ges., xiii., 1883).