1901.] NATURAL SCIENCES OF PHILADELPHIA. 00 



Pityophis catenifer sayi Schlegel. 



Coluber sayi Sch., Ess. Phys. Serp., II, 157 (1837); PituopMs bellona 

 (part), P. McCUUanii and P. sayi B. and G., I. c, 66, 68, 151 ; P. 

 sayi sayi Cope. I. c, 641, and Rep. Nat. Mus., 870 ; Coluber melano- 

 leucus (part) Boul., I. c, II, 68. 



The rostral is narrow above and penetrates the internasals about 

 two-thirds of their length ; an inferior preocular is frequently 

 present; upper labials 8 or 9 ; scales in 27-3o rows, usually five 

 to nine smooth; the dorsal spots are larger and usually fewer in 

 number than in the other forms of catenifer, but an occasional 

 specimen exhibits an equally large number. There are sometimes 

 as few as forty, but two living specimens in my possession show 

 respectively fifty-three and sixty-nine; veutrals 215-230; sub- 

 caudals 50-62. 



The body color is yellowish or reddish brown ; the spots are 

 black anteriorly and more or less blackish brown posteriorly ; the 

 belly is yellowish, with a small dark blotch on the end of each 

 alternate ventral; labials margined with dark brown; the head 

 bauds are usually distinct, but in two large specimens from Pecos, 

 Tex. , they are almost obsolete. The largest I have measured is 

 1,990 mm, (tail 190); greatest circumference 210 mm. This 

 species doubtless reaches a length of over two metres. 



Hab. — The range is very extensive: from Canada to Mexico, 



between the Mississippi river and the Rocky Mountains. It has 



also been taken in Illinois. No. 4,689 Academy collection, from 



Vernon, British Columbia, is not distinguishable from it; in fact, 



in this specimen the posterior extension of the rostral approaches 



melanoleucus. 



PityopMs melanoleucus Daudin. 



Coluber melanoleucus Daud., Hist., des Rept., VI, 409 (1803); Pitu- 

 opMs melanoleucus B. and G., I. c, 65 ; Cope, I. c, 640, and Rep. 

 Nat. 3Ius., 867 ; Coluber melanoleucus (part) Boul., I. c, II, 68. 



In the eastern form the rostral reaches the extreme of elevation, 

 in many cases completely separating the internasals and being iu 

 contact with the prefrontals; usuall}^ four prefrontals; oculars 1-3, 

 sometimes a small sub-preocular; temporals small, 4 (3)-5; upper 

 labials 8; scales in from 27-33 rows, usually 27 or 29, of which 

 in most cases four to seven are smooth (in a large specimen from 

 New Jersey there are seven smooth rows anteriorly and four on 

 the hinder part of the body). 



