Key 



B. Cranial crests straight; head short; leg short; underparts unspotted. 



1. Crests thick, divergent backward from a bony elevation above and 



between nostrils; two large sole tubercles, each with cutting edge. 

 Western Plains and Rocky Mountains. 



Bujo cognatus. (See Colour Plate V, also p. 99.) 



2. Crests narrow, inconspicuous; skin very tubercular, spinous on legs and 



arms; size small (ij inches). Southeastern United States. 



Bujo quercicus, (See p. 104.) 



C. Cranial crests curved around eyes; glands on tibiae; size large. Arizona. 



Bujo alvarius. (See Colour Plate V, also p. 106.) 



III. Parotoids oval (sometimes kidney-shaped in C), extending straight backwards 

 from the posterior angle of the eye. 



A. Head long (three and a half times in total length); cranial crests greatly 



elevated, and swollen into knobs behind; underparts unspotted. 

 Southern United States. 



Bujo lentiginosus. (See Colour Plate IV, also p. 89.) 



B. Head very short (five times in total length); cranial crests variable, 



usually parallel on a raised occiput; underparts unspotted, except on 

 breast; sole tubercles large; size large. Rocky Mountain region and 

 southwards. 



Bujo I. woodhousei. (See Colour Plate IV, also p. 91.) 



C. Head medium in length (four times in total length); cranial crests di- 



vergent behind; warts often large, and arranged singly in dorsal spots; 

 underparts spotted. North America, east of the Rocky Mountains. 

 Bujo americanus. (See Colour Plate III, also p. 6^.) 



D. Head short (four and a half times in total length); cranial crests variable, 



usually parallel; warts never very large, usually arranged several in 

 each dorsal spot; underparts unspotted. Eastern United States, near 

 coast. 



Bujo jowleri. (See Colour Plate IV, also p. 93.) 



E. Head short (four and a half times in total length); muzzle vertical in 



profile; cranial crests parallel; no crests behind eyes; tendency to 

 arrangement of warts in dorsal rows; underparts spotted. North 

 Dakota and Manitoba. 



Bujo hemiophrys. (See p. 98.) 



THIRD KEY. Species of Cystignathid^ 



I. Leg short (length to heel equals length of body forward to ear); muzzle 

 rounded in profile. 

 A. Posterior femur spotted; head long (one-third total length); muzzle 

 pointed, as seen from above; ear round; size small (i^ inches). Texas. 



Syrrophus tnarnockii. (See p. 165.) 



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