17 



shining black, excepting labials, which are white on the 

 lower half with the perpendicular edges black. Anterior 

 part of body beneath, white blotched with gray, becoming 

 a slaty gray posteriorly; chin and throat immaculate white. 

 On the side of the body numerous scales show white edges 

 when the skin is distended. Length, often exceeding five 

 feet. Tail, one-sixth of total length. 



This is our largest species, and is not found in this im- 

 mediate vicinity, but is recorded from the Highlands of the 

 Hudson River. Although resembling in coloration Bas- 

 canion constrictor, it may be easily distinguished from that 

 species by the carinated scales. 



Heterodon Beauvois. 



Body stout ; head but little distinct. Posterior maxillary 

 tooth considerably larger than those in front, but not 

 grooved. Rostral plate upturned, its edge sharp and an- 

 terior surface flat ; an azygos plate behind the rostral. 

 Oculars numerous ; labials not entering orbit. Scales cari- 

 nated. Anal scutum and subcaudals bifid. 



The species have the power of flattening the neck and 

 head to a great extent when annoyed, somewhat resem- 

 bling, in this respect, the species of Naja. 



Heterodon platyrhinus Latr. 

 Hog-nosed Snake. 



Eight upper labials, the sixth and seventh largest. Oc- 

 cipitals about as broad as long. Labials prevented from 

 entering orbit by the numerous orbital plates. Scales on 

 the anterior half of the body narrow, becoming wider pos- 

 teriorly and wide on the tail. Color generally yellowish 

 brown, with dark brown or black irregular transverse 

 blotches ; these often are broken, forming three series of 

 blotches, the dorsal series being largest. Beneath, yellow, 

 with small black spots and blotches. Average length, two 

 to two and a half feet. 



One of the most variable of our species. A specimen 

 from Fort Lee, New Jersey, has the ground color olivace- 



