1925] 
Storer: A Synopsis of the Amphibia of California 
279 
analogue of Lower Sonoran in the west) to Canadian. In California 
the localities in which it has been planted are in the Lower and 
Upper Sonoran zones; two are just at the Upper Sonoran-Transition 
boundary. 
The Bullfrog has been introduced into several places outside its 
own large range. Van Denburgh and Slevin (1921 b, pp. 41-42) report 
that it was introduced into Idaho some years prior to 1916 and was 
then spreading rapidly. They record numerous specimens taken near 
Boise, Ada County. In the Hawaiian Islands several species of 
Asiatic and American frogs have been introduced, including Rana 
catesbeiana (Bryan, 1915, p. 297). The latter is now present in such 
numbers that it is sought commercially, and Hawaiian-grown Bull- 
frogs are to be found at times in the San Francisco markets. 
The Bullfrogs introduced into California have come from at least 
three sources. Those in Sonoma Valley were obtained from a dealer 
in New Orleans and presumably came from Louisiana; those intro- 
duced at Farmington were obtained in Missouri, while the frogs at 
Standard are said to have been obtained from a San Francisco dealer 
who purchased his stock in Hawaii. 
Three specimens of Bullfrog obtained at Mockingbird Lake near 
Riverside presented an appearance suggestive of that of Rana grylio 
Stejneger (1901, pp. 211-215), the Florida Bullfrog. Measurement 
of the Riverside specimens, however, shows that they are to be referred 
to Rana catesbeiana. Similarly, two frogs from the Sonoma Valley 
are catesbeiana. 
Inf e-history. — Little is known as to the details of the Bullfrog’s 
life-cycle in California. In the eastern states the species is almost 
exclusively a pond-dweller and practically never leaves the water. 
The same is apparently the case here. At Ithaca, according to Wright 
(1914, pp. 77-78), the Bullfrog is the last anuran to emerge from 
hibernation, appearing there only when the air temperature has 
reached 69° F. or higher, in May or June. It does not spawn until 
June or July. The early arrival of suitable air temperatures may 
induce an earlier appearance in California. At Searsville Lake, Stan- 
ford University, Mr. Richard Hunt (MS) heard Bullfrogs croaking 
on April 25, 1920. The frogs on Littlejohn’s Creek and at Standard 
are reported not to emerge until April. The frogs reported at Resting 
Springs were heard during April; at Farmington, Bullfrogs were 
heard for a few days during January, 1923. 
