-531- 
I_ . punctoria was found to be well established at the no re recent libera- 
tion point at Atlantic, IT. J., where parasitization by it had reached 2.2 per- 
cent. Initial establishment and maintenance were shown at the Burlington, E.J 
parasite-colonization point, where it was- released in 1938. This pa.ra.site was 
not recovered on the Eastern Shore of Virginia nor at any point in the Lake 
States area. 
Macroc-entrus gifuonsis Ashm . ; --In the 1939 survey M. gifuensls Was found to be 
present in quantity only in southeastern How England, but the data, from this 
area indicated that this polyembryonic ic'hneunonid wa,s the most abundant para.- 
site acting on the borer. It averaged 1C. 6-percent paro.sitiza.tion of all 
borers • observed at the close of 1939. in the southeastern ITew England area, as 
compared to an 3,0-percent average at -the close of 1938. One collection shove 
a. paras itization of 52*4 percent and 1J additional collections ea.ch averaged 
parasitization of the borers of 20 percent or higher by r this introduced para- 
site. It was reared from 6l, or 63.5 percent, of the sample collections made 
the above-mentioned area in 1939 » as compared to only- 49 percent of those ob- 
tained at the close of 1938. M. gifuonsis continued to disperse and occupied 
new territory toward the east and south but no evidence was obtained to indie a. 
further dispersion westward. 
Chelonus annul ipe s Wesm . — This braconid was recovered at the point in Adams 
Township, Lucas Count", Ohio, where it had become initially established in 193 
and where it had been liberated to determine its reaction to the tendency of 
the borer to produce two generations per year in that locality. The survey 
showed that the parasite had increased over 230 percent in abundance. In one 
the collections para.sitiza.tion by this species was 12.6 percent. 
This egg-larval parasite was released in numerous locations in the Connec 
cut River Valley in the spring of 1939 and six of these releases were made wit 
in the territory surveyed in the fall of 1939* Parasite field-status collec- 
tions were made at random without regard to Chelonus annul ip es liberation poin 
yet this parasite was recovered from five widely scattered collections. Such 
general initial establishment had been anticipated, as the releases were well 
synchronized with the presence of host eggs, a condition which, it is known, 
usually promotes recovery during the season of release. 
Eative species- — 'Pour species of native parasites, Bassns agilis Cresson, 
La.brorychus prisnaticus Horton, Aplonya caesar Aid., a.nd Panzer ia peni tails 
Coq. , were recovered in 1939* Their combined parasitization was unimportant. 
Summary 
In the Lake States area the only parasitization of the borer of possible 
economic importance at the close of the 1939 season was confined to areas ad- 
jacent to marshland in the vicinity of southwestern Lake Erie and was produced 
by a single species of parasite, the exotic tachinid Lydella stabulans var. 
grisescens . 
The ectophagous chalcid parasite, Eulophus viridulus , was found to be wid 
spread throughout several counties near Toledo, Ohio, but concentrations were 
low at all points. 
