134 BULLETIN 34, UNITED STATES NATIONAL MUSEUM. 



slenderer aud more vermiform, with much weaker legs than P.glutinosus. 

 Thus in specimens of the two, measuring 1.80 from snout to groin, the 

 head and body of P. glutinosus have the width one-third greater. 



There are eighteen well-marked costal furrows between the limbs, 

 excluding any in the axilla. The posterior are situated in the groin, 

 bifurcating above. In a single specimen of var. Cinereus (Xo. 3805) 

 we reach a count of nineteen. This increase in the number of costal 

 furrows is coincident with the wide separation of the limbs, the distance 

 from head to axilhi being contained about 3^ times in that to the groin, 

 instead of 2|^, as in P. glutinosus. The tail is longer than head and body ; 

 sometimes considerably more so. 



This species, including all varieties, has an extensive range, being 

 found throughout the United States east of the Mississii)pi Eiver. It 

 appears to be more abundant in the Middle States; its northern range 

 is to the middle of Maine, Ontario, and Michigan. 



Its habits are entirely terrestrial, as it is never, even in the larval 

 stage, found in the water. It is abundant under stones and logs in the 

 forests everywhere, and does not occur in open fields. The eggs are 

 laid in a little package beneath a stone in a damp place. When the 

 young emerge they are provided with branchiae, but these soon vanish, 

 and they are often found in this young stage apparently quite devel 

 oped. 



PletJiodon cinereus cinereuo Green. 



The color of the upper half of body and tail is a dark liver-brown ; 

 beneath dirty whitish, finely vermiculated or mottled with brown in 

 about equal proportions, giving rise to a ''pepper and salt" appear- 

 ance. There is sometimes a yellowish tinge towards the head, and a 

 plumbeous under the tail. On the sides the appearance is more that 

 of whitish specks in a dark ground. Sometimes the upper parts are 

 clear brown, at others more or less varied with very minute spots of 

 dull grayish-white. Sometimes the under parts are so much clouded with 

 brown as to appear principally of this color, only faintly mottled with 

 lighter (3805.) 



This species is easily distinguished from P. glutinosus by much slen. 

 derer form, smaller limbs, more webbed digits, eighteen costal grooves 

 stead of fourteen, vermiculated under parts, which have not the black in- 

 ground, the absence of the appearance of pieces of lead foil on the 

 sides, etc. The limbs are very small and weak. The digits are distinct, 

 though short. The basal web extends rather farther forward than in 

 P. glutinosus, the two terminal joints of the longest toes only being free, 

 instead of two and a half. 



I can detect nothing in the characters of head and tongue different 

 from P. glutinosus. 



