AMPHIBIANS 179 



P. nigrita (LeConte). Body like P. feriarum, but with a narrow, 

 pointed head and long legs ; color varying from black to salmon, with 3 

 dark dorsal stripes or rows of spots; length 30 mm.: South CaroUna 

 to Mississippi. 



P. occidentalis (Baird & Girard). Body smooth above, chestnut in 

 color, indistinctly blotched with darker and a dark stripe through the 

 eye and tympanum; length 25 mm.: Georgia and Florida to Arkansas 

 and Texas. 



P. ornata (Holbrook). Body smooth, gray, oHve or reddish brown 

 in color, with or without elongated dark spots and with a black band on 

 each side of the body; several bright yellow spots on the sides 

 posteriorly ; length 35 mm. : Florida and South CaroKna to Texas. 



P. ocularis (Holb.). Color chestnut, with 5 longitudinal stripes; 

 length 25 mm.; upper jaw edged with white: South Carolina and 

 Georgia; the smallest American tree toad. 



Family 5. Ranidae. — Frogs. Medium sized or large Salientia; skin 

 smooth; maxillary and usually vomerine teeth present; pectoral girdle 

 firmisternal (coracoids and precoracoids do not overlap midventrally) ; 

 sacral transverse processes cyHndrical; toes 4-5; no parotoid glands: 

 about 270 species, in all the geographical regions, four-iifths of which 

 are in Africa and India; i genus and 17 species in the United States. 



Rana L. Toes webbed; fingers not webbed; first finger of male 

 swollen, especially in the spring at breeding time; vomerine teeth pres- 

 ent; a pair of conspicuous dorso-lateral glandular ridges (Figs. 93 and 

 94) run the length of the back in most species: about 120 species, 

 widely distributed throughout the world; 17 species in the United States, 

 mostly diurnal and more or less terrestrial animals which live in moist 

 situations on the ground near the water, to which they return to breed, 

 and often also, when alarmed, for protection. The eggs are laid in the 

 water in large jelly masses attached usually to sticks or vegetation. 

 The tadpoles usually complete their metamorphosis the year in which 

 they are born, but the green-frog and the bullfrog do not become adult 

 until the following, or in many cases, the second year. The principal 

 food of frogs is insects, worms and snails. Frogs have a considerable 

 economic importance in consequence of the demand for the hind legs for 

 food, large quantities of which appear in the fish markets of the large 

 cities. 



Key to the United States Species of Rana 



ai In the States east of the Sierra Nevadas. 

 bi Dorso-lateral ridges present (Fig. 93). 



