Bufo Alvarius 



Range: Bufo alvarius is reported from southern California 

 (Fort Yuma) and Arizona (Phoenix). 



There would never be any possibility of confusing this toad 

 with any other. Its green colouration and its smooth skin identify 

 it at once. It is peculiar, also, in attaining a size greater than that 

 of any other North American species. In addition to these, the 

 toad has the following other distinctive characteristics: the con- 

 spicuous glands on the legs, the peculiar white warts at the angle 

 of the jaw, the curving crests of the head, and the greatly diverg- 

 ing parotoid glands. 



The parotoid glands, beginning immediately back of the eye, 

 are so long and descend on the shoulder so much that when they 

 are only three-fourths of an inch apart at their anterior ends, they 

 may be separated at their posterior ends by a distance more than 

 twice as great. The parotoids are about the same width through- 

 out their length. The elevated shoulder-blades show plainly on 

 the back between them. 



The bony crests of the head are smooth and rounded. 

 Although not greatly elevated, they are very conspicuous, because 

 of the smoothness and even colour of the surrounding surface. 

 The crests extend backward from the nostrils in front, diverge 

 and encircle the eyes. There is a crest under each eye in front, 

 and another short one passes forward over the ear, on each side. 

 The skin between the crests on the top of the head is thin and 

 adheres to the bone underneath. 



The ear is unusually conspicuous. It is placed immediately 

 back of the eye, under the anterior part of the parotoid gland, and 

 is surrounded by a prominent ridge. The eye is large and gentle 

 in its expression. The iris is peculiar in having its metallic yellow 

 thickly set with a tracery of bright red veins. There are two 

 curious elevations in the gold of the iris; they are situated in the 

 midline of the eye at the margin of the iris, immediately above and 

 immediately below the pupil. The eyelid is smooth, but is thick- 

 ened, and presents a prominent angle at each extremity. 



The upper jaw projects beyond the lower so that the nostrils 

 are set anterior to the vertical line of the mouth-opening. The 

 oval nostrils are large; they open upwards and backwards. The 

 inner finger of the male is thickened at the base, and the brown 



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