70 IOWA STUDIES IN NATURAL HISTORY 
moved, up hill or down hill, faster or slower.* If the light was 
hidden she would start for the lake, but when the light was pro- 
duced again she would follow it. However, when she was al- 
lowed to get within a few feet of the water the light no longer 
had any fascination for her; she hurried away into the water 
and disappeared from view. 
The number of eggs laid in one clutch varied from six to 
thirteen. The eggs are oblong, measuring from 1.5-2 em. in the 
short diameter to 2.5-3 em. in length, and weigh from 7-12 
grams. When first laid they are somewhat translucent and 
pinkish but later become white and opaque, less turgid and 
somewhat more brittle. The nests are dug out and the eggs 
eaten by some night prowler. One night after a rain some 
twenty out of forty nests were robbed, even though some of the 
nests had been protected by covering them with flat stones. The 
writer has not yet been able to determine exactly the identity 
of the culprit, but on one hillside he counted more than seventy 
nests that had so been robbed, and on another a hundred ten 
nests were dug up and shells strewn around. 
The writer wishes to acknowledge the assistance of Miss Paul- 
ine Kimball, Miss Esther Lusted, and Professor Austin P. Lar- 
rabee in taking notes and watching the time. 
* At times when she was following the light rapidly up hill she appeared to be 
panting. 
