112 DIADOPHIS. 



' ^-§tif StTtfturr 1".'' Genus DIADOPHIS, Baird & Gtirard. 



Gen. Char. Head subelliptical, elougated, depressed, distinct 

 from the body. Cephalic plates normal. Two postorbitals, and two 

 anteorbitals. A well-developed loral. Two nasals ; nostril between. 

 Eyes large. Mouth deeply cleft. Body slender, subcylindrical ; 

 tail tapering. Scales smooth, disposed in 15 or 17 rows. Postab- 

 dominal scutella bifid. Subcaudal all divided. Unicolor above, and 

 generally with a light ring on the occipital region. Abdomen lighter, 

 unicolor, or punctate. 



A. An occipital ring. Eye above the Mi and bth upper lahials. 

 Dorsal scales in 15 roios. 



1. DiadoplliS piuictatus, B. & G.— A yellowish white occipital 

 ring. Body bluish black above ; yellowish orange beneath, with a medial 

 series of spots, sometimes absent. Tail beneath unicolor. Dorsal scales in 

 15 rows. 



Syn. Coluber punctatiis, Linn. Syst. Nat. I, 1776, 376. — Gji. Linn. Syst. 

 Nat. ed. xiii, I, iii, 1788^ 1089.— Harl. Journ. Acad. Nat. Sc. Philad. V", 

 1827, 354; and Med. & Phys. Res. 1835, 117.— Storer, Rep. Rept. Mass. 

 1839, 225.— HoLBR. N. Amer. Herp. 2d ed. Ill, 1842, 81. PI. xviii. 



Spiletes punctatus, Swains. Nat. Hist, of Fish. Amph. & Rept. II, 1839, 364. 



Calamaria punctata, Sohl. Ess. Phys. Serp. Part, descr. 1837, 39. 



Ring-necked Snake. 



Head very much depressed, flattened above ; snout rounded, and 

 overlapping the lower jaw. Vertical plate subpentagonal, tapering 

 backwards, posteriorly acute. Occipitals large, elongated, subangu- 

 lar. Prefrontals irregularly rounded, posterior pair twice the size of 

 the anterior. Rostral broad, but low. Nasal plates large, nostril 

 intermediate. Loral quadrilateral. Two anteorbitals, inferior one 

 narrow and the smaller. Superciliary well developed, broader pos- 

 teriorly than anteriorly. Two postorbitals, inferior one very small, 

 situated above the junction of the 5th and 6th upper labials. Tem- 

 poral shields conspicuous, anterior one larger and elongated. Upper 



