HYLID^E. — CVII. 183 



c. Forehead and crown bony, rough ; skin slightly tuberculate ; sacrum not 

 co-ossified with coccyx; vomer with teeth: heel with a spadelike pro- 

 cess covered by a horny sheath ; toes more or less webbed. 



Scaphiopus, 263. 



263. SCAPHIOPUS Holbrook. (o-Ka(pT), spade ; vovs, foot.) 



515. S. holbrooki Harlan. Spade-foot. Olive brown, a 

 yellowish band on each side. E. U. S., rare W. of Penn. ; bur- 

 rows in the ground ; extremely noisy in spring. " The machinery 

 for producing sounds equal to an ordinary steam whistle is ap- 

 parently confined to the throat of this rare and curious Batra- 

 chian."' (Abbott.) L. 3. (To Dr. J. E. Holbrook.) 



Family CVII. HYLID^l. (The Tree Frogs.) 



Fingers and toes more or less dilated into viscous disks at their 

 tips ; upper jaw and vomer with teeth ; lower parts usually covered 

 with small warts; ear well developed. Genera 14; species 170; 

 found in most warm regions, especially abundant in tropical Amer- 

 ica ; noted for their loud and varied voices, some of them being 

 heard at all times from early spring until frost comes. 



a. Disks small ; fingers not webbed ; palustrine. 



b. Toes broadly webbed ; tympanum indistinct Acris, 264. 



bb. Toes scarcely webbed ; tympanum distinct. . . Chohophilus, 265. 



aa. Disks round, conspicuous ; fingers somewhat webbed ; skin roughened ; 



arboreal Hyla, 266. 



264. ACRIS Dumeril & Bibron. (dicpis, locust, from its 



sharp note.) 



516. A. gryllus Le Conte. Cricket Frog. Hind legs very 

 long. Brownish above; middle of back and head bright green 

 or reddish brown ; a dark triangle between the eyes ; sides with 

 three oblique blotches ; a white line from eye to arm. L. l£. 

 E. U. S., in swamps, not on trees; var. (jryllus, S., N. to S. 111. The 

 northern form is var. crepitans Baird. Its snout i* more blunt and 

 the inner surface of thigh not reticulate; its note resembles the 

 rattling of pebbles. (ypiiWos, a pig-) 



265. CHOROPHILUS Baird. (xopot, chorus; $ t 'Ao?, lover.) 



517. C. triseriatus (Wied). Swamp Tree Frog. Bluish ash, 

 a dark dorsal stripe from snout backward, bifurcating above middle 

 of body; a stripe on each side of this and one on side of head 

 and body, the later pale-edged below. L. 1. Variable. In swampy 

 ground, rarely in trees. Its voice is a " rattle with a rising inflec- 

 tion at the end " (Cope), or like the scraping of a coarse-toothed 

 comb. (Lat. 3-rowed.) 



