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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 13 
egg period was found to average 15.4 days. The two-year larval and 
prepupal stages averaged 432.4 days and in the three-year larvae 761.8 
days. The pupal stage of 106 individuals averaged 30.5 days. Com¬ 
bining the averages of the egg, complete larval, and pupal stages, an 
average period is obtained in this species of 478.3 days in the two-year 
forms, and an average of 807.7 days for the three-year individuals was 
required from egg to adult. 
L. rubiginosa. —Forty-seven beetles of this species were reared from 
egg to adult. Four of them were two-year and 43 three-year grubs. 
The average egg period was 15.8 days. The complete larval stage 
averaged 432.4 days, and 761.8 days in the two and three-year beetles, 
respectively. The average pupal period of 77 pupae was 27.7 days. 
Combining these figures, averages are obtained of 475.9 days for the 
two-year and 805.3 days for the three-year individuals. 
L. futilis .—One three-year grub and 18 two-year grubs of this 
species were reared. The average egg period was 20.8 days, the com¬ 
bined larval stage averaged 415.5 days for the two-year, and 780.3 
days for the three-year grubs, and the pupal average was 25.9 days. 
Averages of 462.2 days and 827 days are obtained for the different 
periods of growth by adding the above figures. 
L. rugosa .—The egg stage of this species averaged 15.9 days, the 
two complete larval periods 415.1 and 767.7 days, and the pupal 
average 30.3 days. For five two-year beetles an average of 461.3 days 
and for 17 three-year adults an average of 813.9 days were required to 
complete development. 
L. implicata .—The combined averages of this species show a two- 
year life cycle of 452.8 days and a three-year cycle of 791.8 days. The 
averages of the stages were computed as follows: egg 18.9 days, larva 
411.7 and 750.7 days, and pupa 22.2 days. 
L. vehemens .—One specimen reared from egg to adult required 845 
days to mature. 
L. submucida .—This species was reared in two years and grubs of 
the same brood are now passing the winter indicating also a three-year 
cycle. The egg stage averaged something over 14 days, the complete 
larval stage 675.5 days and the pupal 21.9, giving a two-year cycle of 
slightly over 711 days as the average of 13 individuals. 
Food Plants 
Adult. —Regular nightly collections on certain designated food 
plants have been made throughout the flight seasons of the adult 
beetles during the past four seasons to determine, if possible, the pre¬ 
ferred food of the adults. Table IX shows the different food plants 
upon which the various species were collected. 
