222 REPTILES OF MASSACHUSETTS. 



men greenish ; its upper portion towards the sides, lighter ; 

 the posterior edge of the abdominal scales, at their union with 

 those of the sides, marked with a black spot ; at the distance 

 of one or two lines within this spot, towards the centre of the 

 abdomen, another spot is observed, which in young specimens 

 is equally dark with the former, but duller in old specimens. 

 Scales oblong, strongly carinated ; smaller upon the back of 

 the head and the upper anterior portion of the body, than far- 

 ther back. Scales of the yellow lateral lines, larger than those 

 of the olive colored back. The scales that are shortest, least 

 carinated, and at the same time the largest, are in a single row 

 between the abdomen and the lateral line referred to. Head 

 flattened, having upon its top ten plates ; one at the snout, two 

 pairs behind this, three between the eyes, and two, larger than 

 either of the preceding, upon the occiput. Pupil of the eye, 

 black ; iris, reddish. Upper jaw margined on each side by 

 seven plates, besides that at the tip ; the fifth, situated directly 

 beneath the posterior angle of the eye, the largest. Lower jaw 

 bordered by ten plates on each side. Two pairs of plates upon 

 the throat, very much elongated. Small teeth in the jaws and 

 upon the palatine bones. 



The bright yellow color, which renders this a beautiful spe- 

 cies when alive, changes to a dull greenish yellow after being 

 immersed in spirits ; in this state, it appears to have been de- 

 scribed by Herpetologists. When the scaly cuticle is remov- 

 ed, the dorsal line beneath is found to be white ; and the sides 

 of the back are of a deep blue color, with two rows of black, 

 nearly circular blotches. Sometimes the line on the back is a 

 greenish white, while the lateral bands are yellow. Upon the 

 occipital plates of one of my specimens are two small yellow 

 spots towards their middle at their interior edges. The 

 brightness of the lateral lines disappears at the anus ; beyond, 

 the color is greenish, and this is gradually lost towards the 

 tail. 



Linnaeus describes his species as having 150 abdominal 

 plates, and 114 caudal scales ; Shaw copies this in his " General 

 Zoology." Harlan makes 150 plates, and 60 caudal scales. 



