640 NORTH AMERICAN SNAKES COPE. 



at maturity. The increase iu the uumber of spots is accomplished by 

 the division of those on the posterior part of the body. 



The number of the labial plates is apt to be unequal on the oi)posite 

 sides. Thus in seveuty-two specimens examined, dfteen have nine 

 labials on one side and eight on the other. The P. catenifer displays 

 the greatest irregularity in this respect, six out of sixteen specimens 

 having labials 8-9. 



Pityophis nielanoleucus Daudin. 



Holbrook, N. Amer. Herpetology iv, 1(S42, p. 7, PI. i ; Bel. aud Gird., N. Amer. Serpt., 

 1853, p. 65 ; Dum. et Bibron, Erp. Gen. vii, p. '23:{, 1854 ; Giiutber, Cat. Col. Serp. 

 Brit. Mus., 1858; p. 86; Cope, Cbeck List N. Amer. Batr. Rept. Bull. U. S. Nat. 

 Mns. I, 1875, p. :^9. 

 Coluber vielanoleucus Dandiu, Hist. Rept., vi, 1803, p. 409 (from Bartram); Harlan, 

 .lonru. Acad. Pbila., 1827, p. 3.59. 



Specimens from Florida have the dark colors rusty or rufus instead 

 of deep brown or black, and the outlines of the spots are not so well 

 defined. 



This species ranges from New Jersey to Florida, preferring the sandy 

 pine woods of the coastal plain. It is the largest snake of this region. 

 It is of a very harmless disposition, and may be handled with impunity. 



Pityophis sayi Scblegel. 



Bd. aud Gird., Cat. Rept. N. Amer., Pt. i, Serpents, 1853, p. 151 ; Cope, Cbeck List 

 Bat. Rept. N. Amer., 1875, p. 39 ; Coluber sa^i Scblegel, Ess. S. 1. Pbysiouomie des 

 Serpents, 1837, p. 157, partim. 



Head with the rostral plate more or less prominent forward and pro- 

 duced and narrowed upwards and posteriorly. Superior labial plates 

 8-8 to 9-9. Scales in from twenty-seven to thirty three rows, keeled, 

 except six rows on each side. Dorsal spots more numerous than in 

 F. melanoleucus varying from fifty to sixty-five on the body, some- 

 times as few as forty. Two to three rows of spots on each side. Gen- 

 erally no subcaudal stripe. Head with three bauds ; one extending be- 

 tween the orbits, one from the orbit directly downwards to the labial 

 border, and one from the orbit to the angle of the mouth. Temporal 

 scales small, generally 3-3 to 4-4; rarely 2-2. 



This species occupies the entire interior of the United States and the 

 Mexican plateau to the valley of Mexico. Eastward it crosses the 

 Mississipi)i River into the prairie country of Illinois. It is represented 

 by two forms, which only differ iu the form of the rostral i)late. One 

 of these (P. s. bellona) inhabits Arizona and New Mexico only, and is 

 intermediate iu character between the typical P. .s. sayi, and the P. 

 catenifer. These forms differ as follows : 



Rostral plate compressed aud produced upwards aud backwards ; ofteu traces of a 

 black subcaudal stripe /'. .v. n<uil. 



Rosiral ])l;itc less coiiiprc3se<l, .lud loss narrowed above; no traces of tbe black sub- 

 caudal stripe /'. .s. bellona 



