1925] 
Storer: A Synopsis of the Amphibia of California 
239 
this species in the same locality in November, 1909. Upon turning 
to the Weather Bureau records, I find that a heavy rainfall, of 2.91 
inches, was recorded for Sierra Madre in November, 1909, whereas the 
average for November is only 1.66 inches. 
So far as my information goes, draytonii spawns only at night. 
I have never found any adult frogs on their spawning grounds during 
the daytime, and the generally reclusive habits of the species at other 
times of the year would suggest nocturnal spawning. Egg masses 
found by nine o ’clock in the morning are usually in the earliest stages 
of cleavage. At the Thornhill pond the masses always have been 
deposited in a shallow overflow area at the western end, which is 
flooded only during the late winter and early spring. During the 
summer months this area is completely dry and covered with a heavy 
stand of tall dock and of milk thistle. About the first of the calendar 
year, in winters of average rainfall, the pond water rises and over- 
flows this area, and in February the frogs resort to this place for 
spawning purposes. Spirogyra and other green algae have become 
abundant in the water and there is a considerable growth of duckweed 
( Lemna sp.). The grasses are then just starting. 
The eggs in this location have been deposited in water from 75 to 
150 millimeters in depth, usually in situations where upon extrusion 
they became attached to dead weed stalks and were supported at the 
surface (pi. 15, fig. 48). The specific gravity of a complete egg mass 
is slightly greater than that of the water, so that some sort of attach- 
ment is necessary to keep the egg mass near the surface of the water. 
On February 6, 1921, three egg masses were found in this shallow 
area. In 1922 visits were paid to the pond at frequent intervals, but 
it was not until the morning of February 21 that egg masses were 
found. On this date, nine masses laid evidently on the nights of 
February 19 and 20 were discovered within a circle not more than 
12 meters (40 feet) in diameter. Each mass was separated from its 
nearest neighbors by 60 centimeters or more. Other egg masses were 
laid in the week following, one or more on the night of February 27 ; 
a visit on March 7 showed that one more mass had been deposited 
during the intervening week. No more fresh masses were found after 
that date. On February 18, 1923, a single egg mass of this species 
was found in the same general location. It had probably been laid 
on the night of February 16. A visit to the pond on March 5 failed 
to show any additional egg masses. 
