POISONOUS SNAKES OF NORTH AMERICA. 401 



Synopsiii of the Crotalid genera inhahitinQ North America north of Mexico. 



rt' Tail without rattle, ending in a point Agkistrodon. 



a- Tail provided with a rattle. 



6' Top of head covered by regular shields SiSTRURUS. 



b~ Top of head covered by numerous scales Crotalus. 



Genus AGKISTRODON,* Beauvois. 

 The Moccasins. 



1799. — Agkistrodon, Beauvois, Trans. Am. Philos. Soc, iv, p. 381 (Type A. 



mokasen Beauv.). 

 1802. — Scytale, Latreille, Hist. Nat. Rept., iii, p. 158 (same type). 

 1803. — Cenchris, Daudin, Hist. Nat. Rept., v (p. .358) (same type; not of Beauv., 



1799). 

 1819. — Sci/talus, Rafinksque, Sillim. Journ., i, p. 84 (emend.). 

 1826. — Tisiphone, Fitzinger, N. Class. Rept., pp. 34, 63 (type T. ctiprea Fitz.). 

 1836. — Acontias, Troost, Ann. Lye. Nat. Hist. N. Y., iii, p. 176 (tyx)e A. leucostoma). 

 ISSG.—Toxicophis, Troost, Ann. Lye. Nat. Hist. N. Y., in, p. 190 (same type), 

 1854. — Anvistrodon, Baird, Serp. N. Y., p. 13 (emend.). 



Si/nopsis of the species of Agkistrodon occurring in the United States. 



aK Aloreal; orbit sejiarated from supralabials by scales; usually 23 scale-rows. 



A. contortrix, 

 a^. No loreal ; supralabials entering orbit ; 25 scale-rows A. piscivorus. 



The Coppekheai). 



Agkistrodon contortrix.f (Linuicus.). 



Plate 3. 



1766. — Boa contortrix LiNN^us, Syst. Nat., 12 ed., r, p. 373. — Scytale contortrix, 

 Latreille, Hist. Nat. Rept., iii, p. 159 (1802). — Cenchris contortrix. 

 Gray, Ann. Philos., 1825, p. — .—Gray, Cat. Snakes Br. Mus., p. 16 

 (1849). — Gray, Zool. Miscell., p. 50 (1842). — Trigonocephalus contortrix, 

 HoLBROOK, N. Am. Herpet, 1 ed., ii, p. 69 (1838).— Holbrook, N. Am. 

 Herpet, 2 ed., iii, p. 39 (1842).— Kirtland, in Mather's Sec. Rep. 

 Geol. Surv., Ohio, 1838, p. 167.— De Kay, Zool. N. Y., iii, p. 53 (1842).— 

 Le Conte, South. Med. Surg. Journ., ix, 1853, pp. 651, 665. — Dumeril et 

 BiBROX, Erpet. Gener., vii,ii,p. 1494 (1854). — Hallowell, in Sitgreave's 

 Exp. Zuni Colo. Riv., p. 147 (1854).— Hallowell, Proc. Phila. Acad., 

 1856 (p. 249).— Jan, Rev., Mag. Zool., 1859, Extr, p. 29.— Jan, Elenc. 

 Sist. Ofid., p. 125 (1863). — Agkistrodon contortrix, Baird and Girard, N. 

 Am. Serp., p. 17 (1853).— Jordan, Man. Vertebr. North. U. S., 5 ed., p. 

 199 (1888).— Hay, Proc. U. S. Nat. Mus., xv, 1892, p. 386.-t-Hay, Batr. 

 Rept. Indiana, p. 123 (1893).— Hurter, Trans. St. Louis Acad. Sc. vi, 

 p. 2,58 (1893).— H. Garman, Bull. Essex lust., xxvi, 1894, p. 36.—Ancis- 

 trodon contortrix, Baird, Serp. N. Y., p. 13 (1854).— Baird, Mex. Bound. 

 Surv., II, Rept., p. 15 (1859).— Cope, Proc. Phila. Acad., 1859, p. 336.— 

 Cope, Bull. U. S. Nat. Mus., No. 1, p. 34 (1875).— Cope, Bull. U. S. Nat. 

 Mus., No. 17, p. 24 (1880).— Cope, Proc U. S. Nat. Mus., X'lv, 1891, p. 

 683 (1892).— Allen, Proc. Boston Soc, Nat, Hist., xii, 1868, pp. 11, 35.— 

 CouES, Proc. Phila. Acad., 1871, p. 48.— Cragin, Trans. Kansas Acad. 



*From the Greek ayKtcrrpov (agkistron), a hook; 66uv (odon), a tooth. 

 t From the Latin contortrix, one who twists. 

 H. Mi8. 184, pt. 2 26 



