62 University of California Publications in Zoology — [Vou. 17 
regions, and both inner and outer metatarsal tubercles are distinct 
and nearly equal in size. The inner metacarpal tubercle is less than 
half the size of the outer. 
Distribution and habitat—The limits of the range of Bufo canorus 
north and south of the Yosemite Park are unknown. The species 
seems to be absent from the high altitudes of Placer County and from 
the Sierras south of the Kings River, where its place is taken by 
Bufo boreas halophilus, which there goes to a high elevation. It is 
the only toad found in the higher parts of the Yosemite National Park, 
where it inhabits wet meadows and lake shores from about 7000 feet 
altitude on Bridal Veil Creek among lodge-pole pines to 11,000 feet on 
the headwaters of the Lyell Fork of the Tuolumne River, near the 
upper limit of the white bark pines. It does not seem to live at the 
lower altitude of the Yosemite Valley proper, where the larger species. 
Bufo boreas halophilus, is found. 
The specific name selected, canorus, refers to the long-sustained, 
melodious trill uttered by this toad. This diurnal singing accompanies 
the breeding activities, which take place as soon as the snow melts 
from the Sierran meadows, June 1 to July 15. Many of the females 
captured at this time contained mature eggs. 
Transmitted October 5, 1916. 
