CROCODILIANS, LIZARDS, AND SNAKES. 963 



Cat. Nos. Gastrosteges. Urosteges. Scales. Length. 



mm. 



13018 150 + 1 29. 877.1 



4433 134+1. 86. 29, 



1639 137 + 1. 60. 29. 



This well-marked species is much less abundant than its allies, the 

 iV'. rhomhifera and N. taxispiloia. The few specimens in the U. S. 

 National Museum come from the three extreme points of the austro- 

 riparian districts, namely, Florida, New Orleans, and southern Illinois. 



The ^^ ej/clopiinn is nearest the N. rhomhifera. The i)atteru of color- 

 ation is quite different, and the scutellation also differs in several im- 

 portant respects. In the X. ciiclopimn the nasal plates are shorter 

 anteroposteriorly, and there are only two scuta which are properly post- 

 ocular. The posterior temporals are smoother and not heeled, and the 

 large scales are emarginate, which they are not in the X. rhomhifera. 



The possession of a series of scales below the orbit, while present in 

 all known specimens of this species, is not confined to it. I have seen 

 it In a specimen of the X. taxispilotaj and it is found in the only known 

 specimen of the Matrix anoscopus- Cope, from Cuba. 



Natrix cj/clopium Dume'ril and Jiihron. 



Two fine specimens of this species from Florida lived for some time 

 in the reptile house of the Zoological Society of Philaclelphia. 



NATRIX RHOMBIFERA Hallowell. 



Tropidonotus rhovihifer Hallowell, Proc. Acad. Nat. Sci. Phila., 1852, p. 177. — 



Coi'E, Check-list N. Ainer. P>atr. Kept., 1875, p. 43. 

 Ti-oi)idonotus fasciatm var. rhomhifer Boulexger, Cat. Snakes Brit. Mus., 1, 1893, 



p. 244. 

 Nerodia rhombifcr B.vihd and Giuard, Cat. N. Amer. Rept., Pt. 1, Serp., 1853, p. 147. 

 Xcrodia IiolbrooJdi Baird and Girakd, Cat. N. Amer. Rept., Pt. 1, 8erp., 1853, p. 43. 



Scales iu twenty seven rows, the larger inferior slightly keeled, the 

 others very strongly, all entire at the extremity. Head very di.stinct, 

 muzzle moderately narrowed. Kostral plate quite or nearly twice as 

 wide as high; loreal short, as high as long; oculars 1-3; temporals 1-3, 

 those succeeding the first keeled. Frontal plate h)nger than wide, but 

 wider than K. sipedon, and superciliaries proportionally narrow. Pari- 

 ietals wide, not elongate, eqnal muzzle from frontal plate. Superior 

 labials eight, the middle of the orbit above the middle of the fourth. 



'To vent; half of tail wanting. 



2 Tropidonotus anoscopus Cope, Proc. Acad. Nat. Sci. Phila., 1861, p. 299. 



