Structure: One to four white warts back of angle of mouth; 

 parotoids large, subreniform, spreading downward on shoulder; large 

 glandular wart on femur and a long one or several shorter ones on 

 tibia; two metatarsal tubercles; two large palmar tubercles; first 

 finger about equal to second; first finger of female may look very long 

 and slender, that of male much heavier at base; palms and soles 

 tuberculate; interorbital much wider than internasal space; a mem- 

 branous fold at the inner edge of the tarsus; horny excrescences on 

 fingers of male may be very prominent, starting from back of wrist 

 and extending all along inner side of first finger and covering upper 

 surface as well; second finger has upper surface with excrescence as 

 well as triangular patch from tip backward; slight on third; tym- 

 panum may be obliquely vertical and elliptical or almost round and 

 very little oblique. 



Voice: There is no good description on record. Miss Dickerson 

 called it a ''gentle chirping," and Ruthven quoting J. J. Thornber 

 wrote, "I assure you there was no lack of noise that day or night, 

 the croaking being incessant." 



Breeding: The probable time is May to July when the summer 

 showers arrive. Sabino Canon, June 1903, "A small stream of water 

 came down from the mountains as a result of rain above, and these 

 toads appeared in abundance, pairing almost immediately. On that 

 day every female was laying eggs. The eggs were laid in the clear 

 stream of water, which was perhaps a foot to eighteen inches deep." 

 (Ruthven quoting J. J. Thornber, 1907, p. 506). 



Notes: "Nothing was seen or heard of them until the advent of the 

 early summer rains which formed a large shallow lake near Buenos 

 Ayres, Arizona. These large toads then filled the air with their loud 

 cries, which increased until a deafening roar was produced. Numbers of 

 them were seen hopping about, but their rarity was not suspected. . . . 



"San Bernadino Springs. July 6, 1892. . . . Lieutenants Gaillard 

 and Irwin and the writer lay down to rest upon the damp grass beside 

 the San Bernadino Springs. . . . At dusk these huge green batrachians 

 began to hop about us, occasionally landing upon our faces." (Mearns, 

 1907, p. 113). 



July 30, 1 917. Just southeast of Tempe, Arizona. In a water hole 

 near a culvert Ralph Wheeler and I caught six immense toads. All 

 males. Probably tardy ones. The tadpoles in the hole are probably of 

 this species. 



We have never seen any Colorado River toad cover itself with 

 secretion as protection from dogs or other animals which might prey 

 upon it, but authentic instances are recorded of death to dogs from 

 seizing them. These toads appear to us Easterners as huge, and several 

 of my campmates at White Sulphur Springs, W. Va., will never 

 forget seeing one of my escaped Colorado River toads hopping 

 through the campfire circle. 



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