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SUMMARY OF SEASONAL HISTORY 
Except for a fev/ individuals that remained active late in May and in 
June, Hy£era brunnelpennis adults were in aestivation from the middle of 
May until late in November, 1939, under the loose bark of growing trees, 
among the dead leaf stubs about the bases of date palms, and to a lesser 
extent in the soil and debris about the bases of trees, in heavily weeded 
areas, and in grassy ditch banks. Emergence of adults from aestivation was 
gradual and was completed by January 1, 1940, the greatest exodus having 
occurred during the first half of December. 
Oviposition began in alfalfa fields about the middle of December, 
was at its height during January and early in February, and gradually de- 
clined to insignificance in early April. Eggs were abundant in sourclover 
as late as the middle of March and declined thereafter, although a few were 
still present as late as May 6. In alfalfa fields eggs were deposited al- 
most entirely in pieces of dead, dry, easily punctured alfalfa stems in the 
surface litter in clusters of 1 to 46. In sourclover patches early ovipo- 
sition was also mostly confined to litter stems, but by the middle of March 
most of the eggs were contained in the living stems, indicating a marked dif- 
ference in the adult reaction toward sourclover and alfalfa. During the cool 
weather of January eggs hatched in about 21 days, but as the weather became 
warmer the time gradually shortened to only 5 or 6 days in early April. 
The larvae matured in 26 to 32 days during the winter months and in 
17 to 22 days during March and early April. The mortality of larvae feeding 
on sourclover in the field was very high and almost complete on alfalfa, 
relatively few finally attaining maturity. By the middle of April very few 
larvae remained either on sourclover or alfalfa. 
A few larvae matured and formed cocoons as early as the end of Febru- 
ary, but the majority matured and formed cocoons during the latter half of 
March and early April. The pupal period lasted about 15 days during early 
March but gradually shortened to 6 or 7 days during April. 
The first new adults were observed on March 13, and emergence was ap- 
parently complete by the end of April, the greatest number having emerged 
from late March to mid-April. By the middle of May practically all the new- 
generation adults had completed feeding and gone into aestivation. Only 
one generation occurred during the year. 
HOST PLANTS 
Adults and lar\ae of Hypera brunnelp ennis have been observed to feed 
on alfalfa (Medicggq sativa) , hubam (annual form of Me lilot us alba) , bur- 
clover (Medicajo his-pjda) , fenugreek (Triponella foenrrr-graecvm) , and sour- 
clover (Melilotus indica) . Of these plants only alfalfa is of economic im- 
portance in the Yuma area, it being the principal forage crop. Hubam and 
sourclover are occasionally planted as green-manure crops but are mostly 
volunteer in citrus and pecan groves and along ditches and roadsides. Bur- 
clover exists only in small amounts, mostly in lawns. To date the growth of 
fenugreek has been limited to a few experimental patches. 
