368 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 17 
fertilized female Tiphia, in a six ounce salve-tin partially filled with soil 
in which were placed three Popillia grubs. Daily examinations were 
made and those larvae on which eggs had been deposited were removed 
to individual tins and fresh grubs placed in the tin with the adult par¬ 
asite. From a total of 363 female Tiphias, 250 of which were reared and 
113 collected in the field, only 25 eggs were deposited on Popillia larvae. 
These were placed on the dorsal side usually between the third and 
fourth segments. From these only one developed sufficiently to start 
spinning a cocoon. It died, however, before the cocoon was completed. 
A large cage was built in which was placed about four inches of soil 
covered with sod and well stocked with third-instar Popillia larvae. 
Over 100 male and female Tiphias were placed in this cage. Several 
plants of Cassia chamaecrista L. were transplanted to the cage in order 
that the adult parasites might obtain their usual food from the extra¬ 
floral nectaries which occur on these plants. Later, upon examination, 
not a single parasitized larvae or cocoon was found, which indicates that 
this species of Tiphia does not readily attack or develop on Popillia 
japonica. Also it was observed in the experiments that iwhen an 
adult female Tiphia was placed in a tin containing three or four Popillia 
and only one Ochrosidia larvae, the egg or eggs laid would invariably be 
placed on the Ochrosidia lavra. This year, however, another Popillia 
larva was found in the field bearing a Tiphia larva on its dorsal segments. 
This parasite developed and formed a cocoon. 
The latter part of August, the male Tiphias were first found in small 
numbers. They later increased in abundance so that in making sweep¬ 
ings with the net, hundreds could be collected. No females were found 
until several days after the meals became numerous. They were then 
obtained in small numbers, later increasing, but never becoming as 
numerous as the males. 
In the fall of 1923, several diggings were made and an average of only 
11 Ochrosidia larvae to the square yard was found. In some plots 
none was present at all, while the most found in any single square 
yard was 25. This was a decided decrease in number as compared with 
last year. However, the number of Popillia larvae was decidedly in¬ 
creased to an average of 142 to each square yard, and in one plot, 
nearly 250 larvae were found. In regard to the Tiphias , cocoons were 
very scarce, averaging only 2 to each square yard. 
Comparing the figures obtained from the diggings made in the autumn 
of 1922 and autumn of 1923, it was found that in the latter season, the 
number of Ochrosidia larvae was reduced 93 per cent, and the number of 
