42 The Peeper, Hyla pickeringii (Holbrook). 



space 1.2 to 2.4, average 1.75; in mouth 0.8 to 1.25, average 0.923. 

 Spiracle sinistral, 2.0 to 2.6 nearer the base of the hind legs than the 

 snout, average 2.16. Anus dextral. Depth of the tail in its own length 

 2.4 to 3.15, average 2.72. Depth of the muscular part of the tail in its 

 depth 1.75 to 2.6, average 2.15. The mouth is contained 1.2 to 2.6 in 

 interorbital space, usually above 1 .5. Greatest length 33 mm. Greatest 

 length of body 11.5 mm. Greatest length of tail 22 mm. Greatest 

 depth of tail 7 nma. 



Coloration of body (Plate ix. Fig. 1 1) : The background of the back 

 is orange, heavily pigmented with dark (almost black) spots, the general 

 tone being greenish; these dark spots are interspersed with very small 

 shining gold-hke ones. The venter is with a cream ground, pigmented with 

 dark toward the sides and more decidedly from the gill region forward. 

 The latter region is conspicuously marked with gold and silver. The 

 whole is iridescent. The muscular part of the tail has an orange back- 

 ground at the base, becoming lighter and almost clean at the tip, the 

 whole pigmented with small spots slightly coalesced. The crests are 

 clear, heavily pigmented with purplish black blotches on the outer edge, 

 particularly toward the tip; but occasionally these blotches are absent. 

 Small gold spots are sparsely scattered over the whole surface. 



Mouth-parts (Plate viii. Fig. 7) : Upper fringe not relatively as long 

 as in Hyla versicolor. The second lateral row extends a considerable 

 distance (sometimes half its own length) beyond end of upper fringe. 

 On the lower lip there are always two rows of teeth, the second row 

 being just inside the second row of papillse. The rows of teeth are 

 quite wavy in general appearance. In most specimens there is a little 

 goatee of teeth on the lip's margin. In 28 tadpoles out of a series of 

 106 this little fringe of teeth is absent and in one case it was divided 

 into two parts; often when it is absent the second row is discontinu- 

 ous and one of the median ends of the second row dips toward the 

 lip's margin. Furthermore, the second row when intact in its middle 

 often bends decidedly toward this region. The upper fringe is rarely 

 broken. In one specimen the lateral upper row of one side was missing. 



THE LARVAL PERIOD. 



This extends over a period of 90 to 100 days. In 1906 the first eggs 

 were recorded on April 14. In the same pond the first transformed 

 individuals were noted 93 days later (July 16). In 1907 eggs were 

 recorded in a pond April 2. In the same place, 94 days later, on July 5, a 

 few were found transformed. In another pond, where they began laying 

 about the middle of April, transformed individuals were recorded 95 

 to 100 days later. In another case, where they began laying April 22, 

 transformed examples were taken July 22, 91 days afterwards. In 

 1908 a period of 100 days was recorded, and in 1911 there was a record 

 of 95 days. In every case cited the period given includes the entire 



