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HyUdae 



THE PACIFIC TREE FROG 

 Hyla regilla Baird and Girard 



Identification Characteristics 



Colour: Extremely variable. Any shade of grey, brown, or 

 green; occasionally distinctly red. A narrow black or dark 

 brown band extends from the nostril (or from ^he muzzle) to the 

 eye, and, widening behind the eye, continues through the ear to the 

 shoulder. This dark band is bordered below by a band of light 

 colour. The immediate line of the jaw is dark. (Fig. i66.") The 

 dark band which passes through the ear may be continued along 

 the sides of the frog in a series of black spots. There may or may 

 not be a V-shaped mark between the eyes, extending well up on 

 the eyelids, and elongated dark spots placed lengthwise along the 

 back and upper sides. Underparts dark or light. Throat of 

 male always darker than remainder of underparts. (Fig. 169.) 

 The undersurface has much orange colour posteriorly. (See 

 Colour Plates VIII and IX.) 



Measurements: Size small, i.e. length \\ to i| inches. Leg 

 long; length of tibia equal to length of femur, and equal to half 

 total length of frog. 



Structure: Skin finely tubercular above, granulated below, 

 except for the throat region. (Fig. 169.) Canthus rosiralis very 

 distinct. (Fig. 165.) Ear distinct, less than half the diameter 

 of the eye. Head obtuse in front. B^sV.s on fingers and toes 

 relatively small. Fingers long, not webbed. Toes webbed half 

 their lengths. (Figs. 169.) 



Range: Hyla regilla has been reported from Washington, 

 Oregon, California, Nevada, Lower California, and from Cerros 

 and Santa Cruz islands, which are twenty miles from the Cali- 

 fornian mainland. This makes its range cover an area from 

 Vancouver Island on the north to Cape St. Lucas at the south, 

 and from the islands of the coast to the eastern base of the Cas- 

 cades and Sierra Nevada. In the region of Washington and 

 Oregon, its range extends well into the desert part of the Great 

 Basin, following the streams of the country. In Death Valley it 

 is found at isolated springs and wells, more than half-way across 

 the Great Basin. There is no authentic report of its occurring in 

 Texas. " Moreover, it may be noticed that in altitude Hyla 



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