Key .... 



II. Ear indistinct; parotoids lacking. 



A. ^Skin smooth; head arched between the eyes in front, sometimes black 



and horny here, and on the end of the muzzle; size small (2 to 2i 

 inches). Western Plains. 



Scaphiopus h. bombijrons. (See Fig. 26, also p. 61.) 



B. Skin rough, with closely set tubercles; head not arched between the 



eyes in front. 



1. Muzzle truncate in profile; short, thick through at end; two or four light 



bands on back present or not. North America, west and south of 

 Rocky Mountains. 



Scaphiopus hammondii. (See p. 59.) 



2. Muzzle rounded in profile; with or without intricate arrangement of 



light bands on back and sides. Southwestern North America. 



Scaphiopus couchii. (See Colour Plate II, also p. 57.) 



SECOND KEY. Species of BuroNiDiE {Toads) 

 I. Parotoid glands short, either roundish or triangular. 



A. Head rounded above, thick through; cranial crests not present; glands 



on tibiae; size large. 



1, Muzzle relatively long, sloping in profile; skin very rough, with warts 



of many sizes; tendency to arrangement of warts in dorsal rows. 

 Northern Pacific region. 



Bujo horeas. (See Fig. 133, also p. 115.) 



2. Muzzle short, steep in profile; skin warty, but relatively smooth on 



and between the warts; femur extremely short. Southern Pacific 

 region. 



Bujo halophilus. (See Fig. 121, also p. 113.) 



B. Head flat, thin through; skin evenly and closely tubercular. 



1. Cranial crests high, sharp-edged, conspicuous. Mexico and Texas. 



Bu]o valliceps. (See Colour Plate V, also p. 108.) 



2. Cranial crests not present; granulations on various parts of head; size 



small (two inches). Southwestern North America. 



Bujo punctatus. (See Colour Plate V, also p. no.) 



II. Parotoids longer, oblique, descending on shoulders. 

 A. Cranial crests not present; skin evenly tubercular. 



I. Head flat and thin through; granulation on muzzle; parotoids unusually 

 large; toad very small (ij inches). Southwestern North America. 



Bujo debilis. (See p. 112.) 



3. Head thick through, short; femur verj* short; sole tubercles unusually 



large; size medium. Mexico and Texas. 



Bujo compaclilis. (See Fig. 93, also p. 102.) 



44 



