CROCODILIANS, LIZARDS, AND SNAKES. 793 



more uniform, although to a considerable size showing traces of the 

 spots on the abdominal scutelhi;. 



Transitions between the Eastern black and the Western green forms 

 of this species are frequently met with in the region connecting the 

 two liabitats. Thus in Michigan the species is generally of a bluish 

 green or greenish blue tint above, and is known as the " blue racer." 

 Similar specimens are in the U. S. National Museum from New Orleans. 

 On th • yellow bellied form of the Plains, Say proposed his Coluber flavi- 

 ventris, which was regarded as a distinct species by Hallowell and by 

 Baird and Glrard. I, however, do not find it to be more than a geo- 

 graphical color race. The same color characterizes specimens from the 

 Pacific district, which are also inferior in size to Eastern individuals, 

 and frequently have the head a little shorter. In spite of this fact 

 they incline to develop an additional labial plate, the number being 

 occasionally in this region eight on one or both sides. Thus of eleven 

 black Eastern specimens only two have eight superior labials on both 

 sides. Of twenty-two yellow-bellied specimens, three have the labials, 

 seven on one side and eight on the other, and nine have eight on both 

 sides. Of the twelve specimens thus exceptional, seven are from the 

 Pacific region and five from the great basin of Nevada and Utah, of 

 the Central region. This is the Bascanium vetustum of Baird and Girard. 

 In the type specimen the sixth upper labial reaches the lower postocu- 

 lar; but this is exceptional and rarely occurs in Californians or other 

 individuals. 



A remarkable color variety of this species was described by me under 

 the name of Bascunium anthicum. In this form the general color is as 

 in the dark-bluish tinted variety, but numerous scales on all parts of 

 the body are a bright yellow. Th > yellow scales are rarely regularly 

 arranged, but sometimes show a tendency to a distribution in chevron- 

 shape 1 crossbauds. A sjjecimen of this kind was sent me by my friend 

 Prof. Pendleton King, from near Baton Rouge, Louisiana. The typical 

 specimen, which is in the U. S. National Museum, is of uncertain 

 locality, but was alleged to have been brought from Siam, most prob- 

 ably erroneously. 



Another color variety is represented by a single specimen (Cat. No. 

 10481) from Galveston, Texas. It is of the yellow bellied type, but the 

 dorsal color is yellowish brown, and small black specks rather sparsely 

 mark the gastrosteges, and from two to four inferior rows of scales 

 throughout the length. The loreal is as high as long, 



A black Zamenis was described by Baird and Girard as having been 

 brought from California, under the name of B. fremontii. The speci- 

 men is a typical Z. constrictor, and was taken probably in the Eastern 

 region. The B. foxii Baird and Girard is the same. 



