348 Illinois Stoi'e Laboratory of Natural Itistory. 



about water, the frogs are very noisy just before dusk, the 

 chorus being broken, however, by longer or shorter inter- 

 vals of silence. A single note is first heard, and, as if that 

 were a signal, it is taken up and repeated by a dozen noisy 

 throats till the air is resonant with the sound. After a time it 

 ceases as suddenly as it began, to be again resumed after a 

 period of quiet. 



Hyla pickeringi, Holbr. Castanet Tree-frog, Piping 

 Tree - frog. 



Hylodes picheringii, Holbr., N. A. Herp., 1842, IV , p. 135, pi. 34.— 

 De Kay, Nat. Hist. N. Y., 1., Zool. III., Kept, and Amph., 

 1842, p. 69, pi. 20, fig. 51. 



Hyla pickeringli, LeC, Proc. Acad. Nat. Sci. Phila.. 1854, VIL, 

 p. 429.— Kenn., Trans. 111. State Agr. Soc, 1853-54, I., p. 593. 

 —Cope, Check List N". A. Batr. and Kept., 1875.— Boulenger, 

 Cat. Batr. Sal. in Coll. Brit. Mus., 2d ed., 1882, Sal. Ecaudata, 

 p. 399.— Yarrow, Check List N. A. Kept, and Batr., 1882.— 

 Davis and Rice, Bull. 111. State Lab. Nat. Hist., I., No. 5, 

 1883, p. 20; Bull. Chicago Acad. Sci., 1883. 



A small delicate species, about .87 inch long. Skin mostly 

 smooth above, granulate beneath and on sides. Palms with a 

 few small tubercles and one large one; base of first finger with 

 a tubercle. Soles smooth, with a well-developed tubercle at the 

 base of the first toe, and a minute one at the bases of the 

 fourth and fith toes, the latter sometimes wanting. Body very 

 slender; head large and long, flat above; limbs slender and 

 weak. Snout produced, distinctly projecting beyond the nos- 

 trils, somewhat angulate. Mandible seen from below rounded 

 in front, the sides less divergent posteriorly than usual; not 

 swollen in front so as to form a knob. Tongue large, obcor- 

 date, notched, and in part free behind. Tympanum slightly 

 elongate vertically, its vertical diameter about two thirds the 

 longitudinal diameter of the eye. Dorsum mostly smooth, with 

 a few granules above each eye. Belly and ventral surface of 

 femora coarsely, throat and ventral portion of the sides finely, 

 granulate. Surface elsewhere smooth. Fingers longer and 

 more slender than usual, the third especially long; web wanting 

 between the first and second fingers, almost imperceptible 

 between the others. Toes also long and slender; webs very 



