
a 9. 
T. R. Gardiner, engaged in receiving, rearing, and distributing 
imported parasites, reports that as a result of extensive scouting for 
adult flies of Dexia ventralis Ald. throughout the season at the Andorra, 
Huntingdon Valley, colonies in Pennsylvania and the Haddonfield colony 
in New Jersey, "apparently there has been a gradual epread, as adults 
were found nearly a quarter of a mile farther than previous records show. 
Grub diggings made at Haddonfield throughout the season showed that prac-— 
tically all grubs were in suitable Stages during the period of adult 
Dexia presence for the first and third generations. However, the number 
of suitable grubs in the soil during the second generation of adults in 
the field the latter part of July and early August was very low. Ap- 
parently this is the main factor which accounts for the great decrease of 
flies in the third generation." 
The year's work with the parasite Tiphia asericae Allen and Jaynes 
is summarized by J. W. Balock, Moorestown, as follows: "One Shipment of 
28,471 cocoons was received during 1931. The emergence from the ship- 
ment received in 1930 totalled 6,154 (54.6 per cent) of which 58.9 per 
cent were males and 41 per cent females. Three colonies were liberated 
from this material. The colony liberated at Andorra Nurseries was 
Scouted but no recovery was made; 684 Autoserica castanea Arrow grubs 
were parasitized by mated females resulting in a cocoon formation of 
55.2 per cent; 576 grubs parasitized by unmated females resulted in a 
50.2 per cent cocoon formation. An experiment run to determine the 
attraction. of Autoserica castanea grubs to T. asericae seemed to indi- 
Caté/that T.saseéricae is not directly .attracted.to ‘itS host, but that 
locating the grub for parasitism by females is more a case of chance 
than of direct attraction." 
Reporting on the lateral migration of grubs of Popillia japonica 
Newm. in soil, I. M. Hawley, Moorestown, says: "A test was started on 
December 14 to determine whether the presence of growing food would have 
an influence on the lateral migration of grubs under greenhouse condi- 
tions. Two bins, each 4 feet square, were filled with dirt to a depth 
of at least 1 foot. In one bin no food was supplied, while in the other 
wheat was planted. After a good root system had developed, 100 grubs 
were placed at a depth of 3 to 5 inches in a trench through the middle 
of each‘bih.: The soil in the bins was kept moist and its température 
was normally between 65° F. and 75° F. Three weeks after the experiment 
started, the soil was removed and the position of each grub recorded. 
It was found that the lateral migration was essentially the same in the 
two bins, but that there was quite a marked difference in the depth of 
the grubs in the two cases. When the roots of wheat were available as 
food, 73 of 85 grubs recovered were in the top 7 inches of soil, while 
only 57 0f 92 recovered were above the 7-inch level, where no food was 
present. In. the series without food 72 of 92 recovered grubs had moved 
more than 8 inches, 42 more than 16 inches, and 17 more than22 inches. 
With food present 62 of 85 recovered grubs had moved more than 8 inches, 
37 more than 16 inches, and 14 more than 22 inches." Mr. Hawley also 
describes experiments in which the groubs migrated, within the confines 
of the bin, a distance of more than 4 feet, and indicates that he pro- 
