292 



distance from the end of the snout, shorter than the parietals ; 

 loreal much longer than deep; two postoculars ; temporals 1+2; 

 seven upper labials, third and fourth entering the eye ; four lower 

 labials in contact with the anterior chin-shields, which are longer 

 than the posterior. Scales in 19 rows, more or less distinctly 

 keeled in the ischiadic region. Ventrals Ids I'nd; anal divided; 

 subcaudals 34-49. Black above ; sides and belly red, with black 

 cross bars or alternating spots. 



Total length 1020 millim. ; tail 150. 



Mississippi Valley and eastwards. 



a,b,c. c? (V. 170; C. 46) New Orleans. M. SalltS [0.]. 

 & ? (V. 189, 191; C. 

 36, 36). 



d. ? (V. 199 ; C. 37), skin N. America. 

 & skeleton. 



e. Yg. (V. 172 ; C. 34). N. America. Mrs. Drummond [P.]. (Tvp<> 



of F. drummondi.} 



f. Yg. (V. 168; C. ?). N. America. Sir K. Murchison [P.]. 



109. PETALOGNATHUS. 



Dipsas, part., Schleg. Phys. Serp. ii. p. 257 (1837J. 



Petalognathus, Dum. fy Bibr. Mem. Ac. Sc. xxiii. 1863, p. 466, and 



Erp. Gen. vii. p. 4G3 (1854). 

 Leptognathus, part,, Giinth. Cat. Col. Sn. p. 177 (1858) ; Jan, 



Elenco sist. OM. p. 100 (1863) ; Cope, Proc. Ac. Philad. 1868, 



p. 107. 



Fig. 21. 



Skull of Petalognathus nebulatus. 



Maxillary short, with 15 or 16 teeth, which gradually decrease 

 in size ; posterior mandibular teeth gradually decreasing in size. 

 Head short and thick, very distinct from neck ; eye large, with 



