Hyla Arenicolor 



bronze. Many minute yellow spots on and between the large dark 

 spots. (Fig. 144.) A white spot under the eye. Orange-yellow 

 at the arm insertion, and on those parts of the femur and tibia 

 that fold against each other. This orange is not spotted or 

 marbled with dark. Underparts light. (Fig. 145.) 



Measurements: Length i^- inches to 2 inches. Head short. 

 Leg to heel measure as long as that of the body forward to the 

 anterior border of the eye. Tibia longer than femur. 



Structure: Skin rough, with small tubercles. (Fig. 143.) 

 Head broad, flat, rounded in front. (Fig. 144.) Throat and 

 underparts granular. (Fig. 145.) Nostrils terminal. Eyes small. 

 Ear two-thirds the diameter of the eye. (Fig. 143.) A fold 

 across the breast and another at the base of the throat. Disk 

 on fingers and toes well developed. No webs between fingers. 

 Web of foot medium in size; two joints of fourth toe free. Inner 

 and outer tubercles present, small (Fig. 146): a prominent tarsal 

 fold. 



Range: Hyla arenicolor is a Mexican form, found also across 

 the border in the United States. It is reported from southern 

 California, New Mexico, Utah, and Arizona. "^ 



Hyla arenicolor resembles the Common Tree Frog (Hyla 

 versicolor) in general appearance and colouring, but is less attrac- 

 tive. The frog is more clumsy, the outlines less delicate, the eyes 

 are smaller, and the colouring is duller. It is somewhat more 

 active than Hyla versicolor and leaps greater distances, as we 

 should expect from the greater length of its legs. 



Its call consists of a series of short notes resembling the 

 bleating of a goat. The throat-sac of the male, inflated during 

 the calling, is dark coloured and large. The throat of the female 

 is white, with spots of dark. Both male and female give a sharp 

 high-pitched cry when taken in the hand. 



The colour is rapidly changeable from grey or brown so dark 

 that it is nearly black, through distinctly spotted phases, to a 

 pinkish or greyish unspotted white. 



^Tucson, White River Canon, Arizona; Santa F^, Fort Wingate, New Mexico; Upper 

 Colorado River. 



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