Bufonidae 



female 4 to 5^ inches. Head short, its length contained in total 

 length nearly five times. (Fig. 68.) A toad having a length of head 

 seven-eighths inch has a width if inch. The length of the leg 

 to the heel equals the length of the body forward to some point 

 between the eye and the end of the muzzle. Tibia but little longer 

 than femur. (Fig. 70.) 



Structure: Skin rough, with rounded warts. Eyelids warty. 

 (Fig. 70.) Parotoids long and oval, not reniform in shape and 

 not descending greatly on the shoulders. Ear a distinct vertical 

 oval, variable in size from a diameter half that of the eye to one 

 which in the case of old specimens almost equals it. The top of 

 the head is usually lifted above the neck region behind. (Figs. 73 

 and 74.) There are two conspicuous bony ridges parallel be- 

 tween the eyes. These may have a groove between them, and 

 may have their edges crenated along this groove (Fig. 70), or 

 they may be obscured by having the groove quite filled up between 

 them. (Figs. 72, 73 and 74.) At right angles behind the eyes these 

 ridges meet two other ridges, each of which extends outward 

 and downward between the eye and the parotoid to the ear 

 on its respective side. Muzzle not projecting greatly beyond 

 the lip. Palm with one large tubercle (Fig. 69), and a smaller 

 one at the inner base of the first finger. Sole of foot rough, 

 with small tubercles. Web of foot relatively short. Inner 

 tubercle usually large, with free cutting edge. Outer tubercle 

 large, but flat, without cr.tting edge. (Fig. 71.) 



Range: This is the common toad of the Rocky Mountain 

 region. It is reported from Montana, Nevada, Utah, Colorado, 

 Nebraska, Kansas, Arizona, New Mexico, and Texas. 



The Rocky Mountain toad is usually dingy in colour. Just 

 after a moult, its colouration becomes brighter and richer in tone, 

 with sharp contrast between the spots and the background. It 

 has great power of change of coiour from light to dark. 



It is related to the American toad (Bufo americanus) , and 

 still more closely to the Southern toad {Bufo leniiginosus), but 

 attains a greater size than either of these. The male of this toad 

 is about the size of the female of the American toad. The relative 

 length of the head and the shape of the cranial crests will always 



92 



