236 Report OF THE DEPARTMENT OF ENTOMOLOGY OF THE 
growing embryo. According to Marlatt® Dr. Potter has stated 
that this change of color is noted at 15 days and after. In 
shape they are oblong, slightly curved and measure about 2 mm. 
( =4; in.) in length (Plate XXII, Fig. 3). They increase in size 
somewhat, probably by the absorption of the juices of the sur 
rounding plant tissue. The period of incubation varies, depend- 
ing apparently upon weather conditions. The usual period is 
probably from six to seven weeks.® 
The larva.—When the larva is fully matured within the egg 
and ready to emerge, the egg shell gives way in a line along 
its back permitting it to escape. The newly hatched larva is ar 
awkward, somewhat spider-like creature measuring about 1.5 
mm. ( ;4 in.) in length. The body is slender and sparsely cov- 
ered with minute hairs. The head, legs and antenne are long in 
proportion. In color it is creamy-white, marked only by deep- 
red eye spots and reddish claws. The most striking peculiarity 
of the insect, both in the larval and pupal stages, is the prom 
inent lobsterlike front legs with which it digs its way into the 
ground. When the larva has gained its freedom it begins te 
move about actively but soon loosens its hold and drops to the 
ground. Owing to the lightness of its body it is not injured by 
the fall. After reaching the ground the first impulse of the 
young larva seems to be to get beneath the surface, for it soon 
seeks some opening by which to enter.’ 
One of the first to investigate successfully the life and habits 
of the larva was Dr. Riley, who undertook to follow the life of 
the insect through until it emerged. His investigations were 
begun in Missouri in 1881, but were finally turned over to a 
Mr. Barlow, who continued them until 1891. During these ten 
years the larve under observation had passed four stages and 
were ready to enter the first pupal stage. These and subsequent 
observations by Marlatt showed that the larve pass the first 
molt during the first year or year and a half, the second after 
an additional period of two years, the third after three or four 
years more and the fourth three or four years later. 
5Tdem., p. 81. 
6Marlatt. Idem., p. 80. 
7Marlatt. U.S. Dept. Agr., Div. Pnt., Bul. 14, n.s., p. 81. 
