
a ae 
methods. Ina recent talk with the man who has had charge of the earwig 
parasite work in Portland for several years it was learned that the par- 
asitic fly Digonochaeta setipennis Fall. is well established in that 
area and that flies and parasitized earwigs are now recovered miles away 
from the point at which parasites were liberated some years ago. Earwigs 
are scarce in Portland this year but the part played: by the parasite in 
this reduction is uncertain. The outlook for control of the earwig through 
parasites is hopeful." 
Lethal effects of dihydrorotenone not impaired by sunlight.—-R.E. 
Campbell and J. C. Elmore, Alhambra, Calif., report that "A small quan- 
tity of dihydrorotenone was exposed to direct sunlight on glass for 30 
hours and 48 imported cabbage worms (Ascia rapae L.) were fed sandwiches 
containing this material. Five worms that ate the smallest quantities 
received. 008, .014, .008, .010, and .015 milligram per gram of body 
weight and none of them recovered. These dosages compare favorably with 
a median lethal dose of .012 worked out for these insects with dihydroro- 
tenone." 
Ratio of sexes of sand wireworm.—~According to J. N. Tenhet, Fair— 
"Horistonotus uhleri Horn maturing in the cages prove that the 
ratio of males to females is approximately 50 to 50. Field collections of 
adults and trapping upon tanglefoot screens indicate that the proportion 
of males to females is at least 25 to 1, but this apparent discrepancy 
must be explained by the fact that the females spend only a very small 
portion of their lives above ground. They burrow into the soil within a 
few minutes after mating and apparently remain in the soil most, if not 
all, of the remainder of their lives." 
Cecil, Ventura, Calif., states that "The wild host plant Lupinus arbo- 
reus has matured one set of pods this season and during the month (July) 
began to send out new flower shoots and set a second crop of pods. 
This is the first time that this plant has been noted as setting two 
crops of pods during a season. The second set of pods on this wild host 
plant will provide additional breeding places for the lima bean pod 
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Hosts of the beet leafhopper in California.--W. C. Cook, Modesto, 
Calif., summarizing data obtained during the past 3 years on hosts of 
Euteitix tenellus Bak., states that "the following conclusions have been 
reached: (1) Atriplex expansa is a rather poor summer host. It carries 
quite heavy populations for one generation in June, but later in the sea- 
thistle, the last two hosts being practically even in possibilities, 
varying somewhat in different seasons; (2) populations on weed hosts tend 
to remain nearly on a level from July 1 to September 1, followed by a 
rapid increase in the fall generations; (3) summer collections by all of 
our various methods in three seasons indicate a normal excess of females. 
