118 [Senate 



Genus BASCANION, Baird & aiRARP. 



Gen. Char. Body slender, elongated r tail very long. Head narrow, deep, 

 long. Eyes very large, Postorbitals 2 : anterior 2; upper very large, 

 lower very small, in a notch between tbe second and tHrd labials. 

 Fourth labial produced up behind the eye, to meet the lower postorbital. 

 Loral 1 ; nasals 2, Vertical much elongated and narrow, concave ex- 

 ternally. Dorsal rows of scales 17, all perfectly smooth and subhexago- 

 nal. Abdominal scutellge 170 - 200 ', posterior one divided : subcaudal 

 90 - 110, all bifid. Colors black or olive ; uniform above, lighter be- 

 low. Skin between the scales black. Young blotched, 



Syn. Bascanion, B. & G. 1. c. 1853, 93. 



12. Bascanion constrictor, B, <^- G. — Blacksnake, 



Sf£C. Chae. Vertical diminisliing for half its length, then parallel. Centre of eye 

 over the fourth labial. In the adult, color lustrous pitch-black; above and be- 

 neath greenish black, sometimes tinged with greenish white : chin and throat 

 white. The young are olive, with rhomboidal dorsal blotches ; beneath greenish 

 white. 178+1, 93, 17, 40^, lOf (Penn.). 



SYNONYMS. 



Coluber consti idor , Linn. Syst. Nat. I. 1766, 385. — Gm. L. Syst. Nat. ed. xiii. 

 I. iii. 1788, 1109.— Harl. Journ. Acad. Nat. So. Philad. V. 1827, 348; and 

 Med. & Phys. Res. 1836, 112.— Schl. Ess. Phys. Serp. Part, descr. 1837, 133, 

 pi. V. f. 3 and 4. — Stoker, Eep. Kept. Mass. 1839, 225.— Holer. N. Amer. 

 Herp. III. 1842, 55, pi. xi.— Thomps. Hist, of Term. 1842, 117.— Dekay, N. 

 York Fauna, Kept. 1842, 35, pi. x. f. 20. 



Hierophis constrictor, Bonap. Fn. Ital. II. 1841, Art. Col. leopard. 



Vipera niger, Catesb. Nat. Hist. Carol. II. 1743, 48, tab. xlviii. 



Blacksnake, Kalm, Reise N. Amer. II. 1764, 202.— Penn. Arct. Zool, Suppl. II. 

 1792, 92. 



Bascanion constrictor, B. & G. 1. c. 1853, 93. 



The blacksnake, or blue racer, is well known to every one, from its abun- 

 dance and marked traits of character. It ranges over the whole United States 

 east of the Missouri river : how much further west it extends, is not yet 

 ascertained. 



