Reptiles and Ampliihians of Illinois. 335 



seal knob. P]yes large. Parotids large, elongate, imperfectly 

 elliptical. Tympanum circular or slightly elongate vertically, 

 its diameter a trifle greater than half the longitudinal diameter 

 of the eye. Vocal sac of male opening by two large slits in the 

 floor of the mouth, one on each side, just within the mandible. 

 Legs short and very stout. Fingers a little depressed, with a 

 few small tubercles beneath. First finger projecting nearly at 

 a right angle to the others, and more enlarged at the base than 

 they ; the third finger longest. Palm with a large round 

 callosity. Toes depressed, partly webbed, the first the shortest, 

 the fourth much the longest. A large flattened process arises 

 on the under side of the foot at the base of the first toe; on 

 the outer side of the foot is a callosity about half the size of 

 that on the palm. 



The color varies with age and locality. The general color 

 of adults is olive, or reddish or gra3nsh brown above, with a 

 narrow vertebral pale line and with spots of dark brown or 

 black, margined with pale; pale below, immaculate or spotted 

 with black. The color of the upper surface in old specimens 

 is often so dark that the markings cannot readily be discerned. 

 On well-colored specimens of medium size the following marks 

 may be seen: Two small vertically elongate spots, one on each 

 side of the middle line below and inside the nostrils; a quad- 

 rangular spot below the eye; a small spot between the latter and 

 the elongate spots; an elongate spot between the anterior angle 

 of the eye and the nostril; a large elongate spot extending from 

 the inferior posterior rim of the eye to the angle of the mouth; 

 two spots on the head, sometimes united and forming a band 

 between the anterior angles of the eyes; two elongate spots, 

 one on each side, lying on the lid of the eye and extending 

 obliquely backward across the cranial ridges nearly to the me- 

 dian pale stripe; two small spots, one for each side, at the upper 

 anterior margins of the parotids; two small spots near the 

 median line, about opposite the middle of the parotids; two 

 large spots, one for each side, near the upper posterior margins 

 of the parotids; then follow several spots of different sizes on 

 each side of the median line, and outside these are still others. 

 All these spots on the back have a narrow pale margin. Under 

 surface pale yellowish or whitish; immaculate or spotted with 



