Bufo Cognatus 



This toad differs from the species of the Pacific Slope (Bufo 

 boreas) in the possession of bony ridges on the head, while it is 

 like them in skin structure and arrangement of warts. It differs 

 from the species of the Rocky Mountains and Western plains (Bujo 

 I. woodhousei and Bufo cognatus) in having the underparts conspicu- 

 ously spotted and in the arrangement of the cranial crests, but 

 agrees in certain features, such as the foot structure. The species 

 bears a superficial resemblance to Bujo fowleri. 



BUFO COGNATUS, SAY 



IDENTIFICATION CHARACTERISTICS 



Colour: General colour may be brown, of light or dark shade ; 

 grey; or green, dull or brighter. There is a light vertebral streak. 

 The toad may appear striped or spotted, depending on whether the 

 dark spots or the light borders of the spots are more conspicuous 

 at the 'time. Specimens from Arizona tend to have the spots 

 more emphatic; specimens from Colorado more often appear 

 striped. (Compare Figs. 89 and 90, also 91 and 92. For one phase 

 of colouration, see Colour Plate V.) 



The arrangement of the spots may be as follows: One ob- 

 liquely set above each eye ; one on the back, just within the parotoid 

 gland on each side; three oval spots set obliquely and ranging 

 along each side of the vertebral streak. Two similar spots back of 

 and in line with the parotoid gland, and two or three others on the 

 upper sides. Other more obscure spots may be present. Under- 

 parts light, unspotted; yellow posteriorly. Much yellow (especi- 

 ally in the case of young toads) on palm, sole, and on concealed 

 surface of femur. Ends of fingers and toes dark-coloured. 



Measurements: Size large, i.e. length 3 to 4^ inches. Head 

 short, wide; small for the size of the toad. The length of the head 

 is contained in the total length about five times. A toad 4^ inches 

 long has a length of head of inch only. Legs very short, femur 

 scarcely visible outside of the skin of the body. (See Figs. 88 and 

 89.) Tibia somewhat longer than femur. Foot extends consid- 

 erably beyond the knee when the leg is folded. (Fig. 91.) 



Structure: Whole upper surface, including the eyelids, set 

 rather closely with warts, some medium-sized and some small. 

 Often the larger of these warts are set in wreaths around the inner 



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