Pelobatidse 



to heel equals length of body forward to ear or eye. Tibia shorter 

 than femur. (Fig. 24.) 



Structure: Skin rough, with small tubercles on head, back, 

 sides, and tibias. Skin of underparts slightly rough, smooth an- 

 teriorly. Parotoids small, flat, covered with tubercles; indis- 

 tinct. Head rounded in front; slight indentation in upper jaw. 

 Muzzle slightly projecting, with gradual slope to the jaw. Ear 

 round, indistinct. Pupil vertical, with narrow slit in iris below. 

 Iris has triangular indentation at front. Nostrils nearer to the 

 end of the muzzle than to the eye; they are directed upwards. 

 Hand with one large and two small palm tubercles; third finger 

 longest; first and second black and horny (male). Foot large, 

 fully webbed, and supplied with a large black inner sole tubercle. 

 (Fig. 25.) 



Range: Scaphiopus couchii (Baird) is reported from Mexico, 

 Lower California, and Texas. In Texas, it has been found at 

 Brownsville, Waco, and Helotes. 



This Southern Spadefoot is an attractive and alert-looking 

 creature, very different from the uncanny, smooth-skinned Eastern 

 Spadefoot (Scaphiopus holhrookii) and the Northwestern form 

 Scaphiopus h. hombijrons. It is often very bright in its colour- 

 ation and shows habits of jumping and walking instead of con- 

 stantly burrowing; it would thus seem more adapted to terres- 

 trial existence than are its near relatives. The adaptations for 

 subterranean and nocturnal life are well marked, however, in the 

 development of the inner sole tubercles and in the vertical pupil 

 of the eye. 



There is great variation in the arrangement of the colour. 

 The bands of light may be so reduced as to give an irregularly 

 spotted appearance merely. On the other hand, they may be 

 so broad as to make the creature appear light-coloured banded 

 with dark. The typical arrangement of the light is as follows: 

 A curved or V-shaped band between the eyes anteriorly, with the 

 bend pointing backwards; second and third larger, more elon- 

 gated V-shaped bands more or less parallel to this, starting back- 

 ward from the eyelids on the top of the head posteriorly and from 

 the posterior angles of the eyes respectively. The third meets, 

 in the midline of the back, oblique converging bands from the 



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