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The newly hatched first-stage larva is about one thirty-second of an 
inch in length. The body color varies from yellowish to light gray and the 
head is black. After feeding for a time the larva increases in size and the 
body usually assumes a somewhat dingy-gray color; the head remains black. 
Immediately upon molting to the second stage the larval head is yel- 
low, as it is after succeeding molts, but soon becomes dark. The body is 
dingy gray, but a few individuals acquire a faint greenish tinge immediately 
before molting to the third stage. 
The head of the third-stage larva is mostly black but with traces of 
brown about the center. Its body is light green with a readily visible white 
stripe down the middle of the back. 
The head capsule of the fourth-stage larva is almost entirely brown 
but with noticeable darkness about the edges, especially posteriorly. The 
body is light green with a broad white stripe down the middle of the back 
paralleled by smaller but distinct white stripes on each side. A limited 
number of measurements showed a range in body length from one-fourth inch to 
almost one-half inch; the average body length was four-tenths of an inch. 
Larvae of Hypera brunneipen nis are similar to comparable stages of 
H. postica , and no distinguishing characteristics were discovered. 
Feeding Habits of Larvae 
Newly hatched larvae preferred the tenderest portions of host plants, 
usually being concentrated in the buds or stem tips and sheaths at the base 
of stems. Many small larvae buried themselves in these tissues and remained 
hidden for short periods while feeding. Second-stage larvae fed in a similar 
manner but were usually more easily observed than the smaller first-stage 
larvae. Comparatively few of either stage could be collected by net-sweeping 
of plants. 
Larger third and fourth instars also fed upon the tender portions of 
plants but most heavily upon the open leaves. Alfalfa leaves were skeleton- 
ized by intensive feeding, leaving only the principal leaf veins and some- 
times portions of the lower epidermis. Larger larvae, however, feeding upon 
the thicker leaves of sourclover and hubam, tended to consume all the leaf 
tissues, making clean holes or completely removing portions of the leaves, 
thus giving a ragged appearance to the plant. In general, larvae concentrate 
first upon the uppermost portions of plants and move downward as the foliage 
is destroyed. In the manner of feeding and damage inflicted Hypera brun- 
neipennis appears to be identical with the alfalfa weevil (H. postica ) on 
alfalfa. 
Larvae that become dislodged from plar.ts readily ascend and feed upon 
the nearest available host plant. They are capable of crawling short dis- 
tances over dry exposed soil, if not too hot, and also over soil following 
irrigation. Larvae have been observed actually to remain in water for short 
periods and, after its subsidence, to ascend and resume feeding on the near- 
est host plant. 
