184 BATRACHIA: SALIENTIA. — XXVII. 



266. HYLA Laurenti. (uXi;, forest.) 



518. H. versicolor Le Conte. Common Tree Toad. Green, 

 gray or brown, with irregular dark blotches ; below yellow, behind 

 white; tympanum f diam. eye ; fingers J- webbed; skin with small 

 warts. L. 2. E. U. S., W. to Kan., very abundant and variable. 

 Its " clear, loud trilled rattle " is heard mostly in the evening and 

 in damp weather. 



519. H. pickeringil Holbrook. Yellowish brown or fawn-color, 

 with dusky rhomboidal spots and lines, the latter usually arranged 

 in the form of an oblique cross ; head with lines ; limbs barred ; 

 tympanum very obscure. L. 1. E. U. S. 



520. H. squirella Daudin. Olive green, with irregular dark 

 blotches ; a dark bar between eyes ; a white line along upper jaw 

 to shoulder ; greenish white below, darker beliind ; throat with a 

 few dark spots ; legs marked with darker above ; tympanum half 

 diam. eye. L. 1\. Ind. (Brookville, A. W. Butler) to S. C. (Eng. 

 squirrel.) 



521. H. andersonii Baird. Deep pea-green; sides with irre- 

 gular yellow spots ; a green spot on throat ; a purplish band from 

 eye to arm ; tympanum J- eye. L. 1^. N. J. to S. C, rare. 



Family CVIII. ENGYSTOMATID^. (The Toothless 

 Frogs.) 

 Frog-like Batrachians with the maxillaries toothless and the 

 diapophyses of the sacral vertebrje dilated. Genera 18 ; species 

 54, chiefly tropical. 



a. Pupil erect; tongue elliptical ; tympanum hidden; toes free; no preco- 

 racoids Engystoma, 267. 



267. ENGYSTOMA Fitzinger. (iyyis, contracted ; irroiui, 

 mouth.) 



522. E. carolinense Holbrook. Snout obtuse, not twice eye; 

 skin smooth, a fold across head behind eyes. Brown, dotted with 



er below. L. 1. S. U. S., N. to Mo. 



Family CIX. RANID^. (The Frogs.) 



Teeth well developed on upper jaw, and usually on vomer also; 

 toes 4-5, all more or less webbed; ear well developed. Genera 18, 

 species 250, chiefly of the Northern Hemisphere and the East 

 Indies. Most of them are aquatic, and similar to our common 

 frogs. 



a. Vomerine teeth present; no finger opposable to the others; tongue emargi- 

 nate behind ; hind toes full-webbed Rana, 268. 



268. RANA Linn»us. (Lat., frog.) 



a. Glandular folds on each side of back more or less distinct ; web of feet not 

 reaching tip of fourth toe. 



