TBEE-TOAD 663 



The eggs of the tree-toad are laid during the spring months. No egg 

 masses were seen anywhere in the region, but it seems likely that the 

 individuals living in the higher altitudes spawn at much later dates than 

 those in the lowlands. On August 20 and 23, 1915, at Merced Lake, small 

 tree-toads, measuring between one-half and three-fourths of an inch in 

 length, were found in numbers. These were animals which had but recently 

 changed to the adult condition, and which had undoubtedly come from 

 eggs laid during the same season. 



Among the specimens of this species collected in the Yosemite region 

 are two individuals taken at Merced Grove Big Trees and Porcupine Flat, 

 respectively, which after being preserved are nearly 2 inches (1% and 

 li^e) in total length and are fully as large if not larger than any we 

 have seen from anywhere. The cup-like discs or pads at the ends of the 

 toes on these animals are unusually large and conspicuous and in life must 

 have been fully twice the diameter of the toes themselves. 



In Yosemite Valley on October 13, 1915, scores of half-grown Hylas 

 were seen in a saw grass swale. There were also many grasshoppers there 

 and it was often difficult to distinguish a toad from a grasshopper until the 

 individual Avas scrutinized closely. The tree-toads exhibited much variation 

 in color, ranging from uniform bright greenish yellow to dark brown ; some 

 were coarsely mottled with dark and light brown. 



Yellow-legged Frogs. Rana boylii Baird** 



Field characters. — No conspicuous raised glands on hind neck or back; hind toes long 

 and slender, fully webbed, without discs at tips. Total length 3 inches or less. Upper 

 surface of body rough-surfaced, with scattered low points. (See pi. 60&.) Coloration 

 above blackish, dark green or brown, with markings few and indistinct; lower surface 

 yellow or whitish, sometimes mottled on throat. No light line along upper jaw; ear 

 region not darker than rest of head. 



Occurrence. — Common resident practically throughout the Yosemite region. Recorded 

 from Pleasant Valley, eastward to near Mono Lake. In Transition Zone on both sides 

 of mountains, and in Upper Sonoran on west side, is subspecies boylii; in Canadian and 

 Hudsonian zones is subspecies sierrae (see footnote for details). Lives in, and on the 

 banks of, ponds and streams. 



44 Two subspecies of Yellow-legged Frog are found in the Yosemite region. These 

 occupy separate parts of the region and also present characters which make possible 

 identification in the field. 



California Yellow-legged Frog, Rana hoylii hoylii Baird, resident throughout the 

 Upper Sonoran Zone of central California, was found at Pleasant Valley and thence 

 eastward to near Feliciana Mountain and to Smith Creek, east of Coulterville ; it recurs 

 in vicinity of Mono Lake (Farrington Ranch). It is distinguished by having many 

 small points or roughnesses on the ear membrane and by a relatively long hind leg 

 (when leg is bent forward the bent 'instep' reaches to or beyond nostril). 



Sierra Yellow-legged Frog, Eana boylii sierrae Camp, resident in boreal portions 

 'of the Sierra Nevada, was found in the Canadian and Hudsonian zones from Peregoy 

 Meadow and Porcupine Flat eastward to Tuolumne Meadows and the head of Lyell 

 Canon. It has a relatively smooth ear membrane, and when the hind leg is bent forward 

 the bent 'instep' does not usually reach beyond the nostril. 



