572 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 17 
There might be added to the above names a long list of growers in the 
Santa Clara Valley who have increased their crops by spraying with 
heavy miscible oil, but the above should be sufficient to convince the 
most skeptical. 
LIFE HISTORY AND BIOLOGY OF ECHOCERUS CORNUTUS 
(FAB.) 
By David Shepherd, Stanford University 
Abstract 
Echocerus cornutus, a cosmopolitan bran beetle is found injuring cereal products. 
A description is given of the various stages of the insect together with notes on life 
history and food habits. 
Results of experiments to test the attraction of water for these insects and the 
effect of air-tight sealing on the life of the insect, and the effect of humidity on the 
rate of development, are given. 
Echocerus cornutus is cosmopolitan in its distribution but according to 
available data is injurious to cereal products, in the United States, only 
in the coast and bay regions of California. In spite of its economic im¬ 
portance, the literature dealing with this Tenebrionid has done little in 
furnishing information as to its life history or general habits and for that 
reason the following condensed account of the study and observations of 
this beetle is given. 
The Egg. The egg is oval elliptical in longitudinal section and its 
size when coated depends upon the size of the particles of the material 
in which it is deposited, the actual measurements showing it to vary 
from .48 mm. to .51 mm. in width and from .85 mm. to .93 mm. in 
length. 
When first deposited the egg is of a pure white glistening color, 
covered with a viscid substance showing a series of fine lines circling it 
radially, this being its complete sculpturing. After the egg has been 
deposited for some time it changes in color from the pure white to a 
straw color. 
The eggs are ordinarily found among the particles of material in 
which the beetles live. In some instances they have been found adhering 
to the side of the carton or container in which the material has been 
placed. 
The Larva in its Last Instar. The larva in its last instar is elongate, 
subcylindrical, convex dor sally and slightly convex ventrally. In 
color it is yellowish, the ventral surface being lighter in color than the 
dorsal. The head and the posterior portion of the larva are darker in 
