Pelobatidse 



ern California, New Mexico, Texas, Utah, Nevada, northern Cali- 

 fornia, and Washington.^ 



This Western Spadefoot resembles Scaphiopus couchii in 

 having a tubercular skin and the parotoids either obscure or 

 lacking. It differs in having a more pug-dog expression pro- 

 duced by the shorter, more truncate, and projecting muzzle; also, 

 the ear is more obscure. There can never rise confusion in dis- 

 tinguishing it from Scaphiopus holbrookti or Scaphiopus ham- 

 mondii hombijrons, both of which are comparatively smooth- 

 skinned. The lack of parotoid glands and black granulations 

 of the head will also distinguish it from Scaphiopus holbrookti, 

 and it differs from hombijrons in having the cranium between the 

 eyes flat instead of arched. 



There is considerable variation in colouration and in size in 

 the species. The pattern of dorsal lines may be present in whole 

 or in part only, or may be obscured. The northern specimens 

 attain a larger size than those in southern California and Texas. 



This species, like the other Spadefoot Toads, is interesting 

 because of its adaptation to existence in dry regions. It remains 

 in subterranean burrows throughout the year except during con- 

 tinued or heavy warm rains. It is said to be very noisy dur- 

 ing the breeding season. Young specimens were obtained from 

 San Diego, California, in early April. They measure three-fourths 

 inches long, having a blackish skin already covered with reddish 

 warts, and feet that show the black horny spade well developed. 

 They have the characteristic thick projecting muzzle and obscure 

 tympanum. 



Scaphiopus hammondii has been known to deposit its eggs in 

 pools formed by heavy rains, in July and August. It is likely 

 to appear in gardens and vacant lots in cities as well as in more 

 isolated country places. 



I San Diego, Olancha, Redding, California; Painted Desert, Arizona; Helotes, Texas; Pyramid 

 Lake, Nevada; Salt Lake City and Provo, Utah; Fort Walla Walla, Wash. 



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