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University of California Publications in Zoology [Vol. 27 
may be cited as bearing on the nocturnal activities of this species. 
These animals were taken alive to Berkeley where they were kept for 
a month or so in a metal box provided with a layer of earth several 
inches in depth. At first the box was covered by a glass plate ; later, 
a tight-fitting tin lid was used which excluded practically all the day- 
light. Examination of the box by day when the glass lid was in use 
revealed none of the toads and the same was usually true when the 
tin lid had been down; the spadefoots had burrowed into the dirt. 
But each night, after dark, they were to be found out on top of the 
earth. The light of an electric bulb held over the box at night was 
usually sufficient to stimulate digging movements. 
When in the dark the golden-spotted iris of the spadefoot ’s eye is 
completely relaxed so that the eye appears entirely black, but within 
a few seconds after one of the animals has been brought into light of 
any considerable intensity the iris begins to contract toward a vertical 
ellipse. In the strong sunlight of midday the aperture is reduced to 
a narrow vertical slit. I do not recall any other local amphibian 
which has so pronounced a diaphragm reaction. 
No information is at hand to indicate the nature of the retreats 
occupied by the Western Spadefoot in California. The eastern species 
($. holbrookii) has been known to excavate short pyriform retreats 
(Dickerson, 1906, p. 57). An example of S. hammondii captured near 
Santa Maria by Mr. L. N. Crawford on April 14, 1923, was released 
in the garden of his residence on the morning of April 17. By noon 
it had dug to a depth of 4 inches ; by evening it had gone down too 
deep to be unearthed. 
Most of the Western Spadefoots w T hich have been collected in Cali- 
fornia have been come upon by naturalists who were in the field imme- 
diately following late spring or summer rains when the animals were 
out to spawn. Occasionally they have been captured in traps set for 
small mice. In this manner Mr. Joseph Dixon obtained two S. ham- 
mondii in the vicinity of Mono Lake. In northwestern Nevada, Taylor 
(1912, p. 345) has reported the capture of one individual in a mouse- 
trap and of two others which were abroad at the breeding season. 
The voice of the Western Spadefoot Toad is to be heard only 
during a brief season each year, when the adults appear aboveground 
for spawning* purposes. Unlike some of our other Salientia, this 
species does not call over a long period. Camp (MS) records hearing 
the notes of males in the vicinity of Sierra Madre on March 3, 4, and 6, 
1909, on May 11, 1913, and in May, 1914. On July 4, 1909, in the 
