146 University of California Publications in Zoology [Vol. 27 
banks were heavily forested. Like Rana boylii in California, Ascaphus 
lives solitarily in the stream or no farther away than the adjacent 
shore. The adults take shelter under stones in the water and when 
these are lifted the toads either remain motionless on the bottom or 
else float passively downstream amid the debris. When removed from 
their native habitat the adults perish quickly unless kept in melting 
ice water or in a refrigerator. A very low thermal death point is 
indicated, probably the lowest for any amphibian living in the United 
States. 
Two instances have been recorded of the finding of Ascaphus out 
on land away from streams. Van Winkle (1922, pp. 4-6) found three 
individuals among fallen timber and underbrush on a wooded moun- 
tain slope near North Bend, Washington; there had been a heavy rain 
the night before and the moss, brush, and trees were wet. In a note 
appended to the foregoing account G. K. N[oble] . gives the experience 
of Mr. Philips G. Putnam, who, following several days of rain, found 
four Ascaphus out on land, one of them over 100 feet from the stream. 
This particular toad had not begun to absorb the larval tail. 
No mention is made by either Van Denburgh or Gaige of a vocal 
sac, nor is one to be seen on specimens at hand from Lake Cushman. 
Presumably the voice has degenerated, being of no value to a species 
so strictly aquatic as Ascaphus. Males of the European species of the 
Discoglossidae, which are of terrestrial habit, have voices like other 
Salientia. The reduction in voice of Rana boylii and Rana draytonii 
in California may be a parallel development to that in Ascaphus. 
Breeding males, according to Gaige (1920, p. 5), have the forearm 
enlarged to two or three times the normal size, the inner palmar 
tubercle is similarly increased and where the latter touches the fore- 
arm a white horny patch is developed; several individuals had this 
patch, the inner side of the first two fingers, and the inner palmar 
tubercle, covered with black. The underside of the forearm becomes 
gray thickly dotted with white. 
Gaige found females containing eggs and males showing the highly 
developed secondary sexual characters of the species from June 27 to 
‘ ‘ early September, ’ ’ which she interprets as meaning a prolonged 
breeding season. Eggs were found in a creek on August 5, and a 
full-grown tadpole was collected on June 25. This latter individual 
was 45 millimeters in total length. Although no dates or localities 
are given regarding tadpoles, one gets the impression from reading 
Gaige ’s account that they were found at various dates through the 
season. 
