136 
BULLETIN 1476, U. S. DEPARTMENT OF AGRICULTURE 
York State, but less than 1 per cent of the hosts collected were 
parasitized by this species, and no other parasites have been recorded 
in this area to date. Table 45 summarizes the results of the collec- 
tions of P. nubilalis larvae and pupae in New England to determine 
j>arasitism during the period from 1919 to 1921, inclusive. 
Table 45. — Parasitism of Pyrausta nuMlalsis larvae and pupae by various 
Diptera and Hymenoptera in New England 
LARVAL COLLECTIONS 
First generation 
Second generation 
Year 
Number 
collected 
Number Per cent Number 
para- of para- £E{S 
sitized sitism coll ected 
Number 
para- 
sitized 
Per cent 
of para- 
sitism 
1919 
5,525 
4,741 
7,577 
80 1.45 ' 6,231 
68 1.43 i 17,951 
133 1.75 4,241 
2 
49 
22 
03 
1920 
27 
1921 
.52 
Total 
17, 843 
281 j 28,423 
1.57 ! 
73 
Average _ 
.26 
PUPAL COLLECTIONS 
1920 - 
536 
2,905 
27 
65 
5.04 
2.24 
4, 497 
2,801 
6 
4 
0. 13 
1921 
.14 
Total 
3,441 
92 
7,298 
10 
2.67 
.137 
These figures on parasite rearings do not, of course, show the 
actual percentages of the host killed under field conditions by the 
action of parasite adults and from which no parasites are reared, but 
it is evident from the data in Table 45 that but little help can be 
expected of the native parasites of the larva and pupa in suppress- 
ing P. nubilalis. 
FOREIGN PARASITES 
Foreign literature contains very few records of parasites bred from 
P. nubilalis in any of its stages, and most of the literature dealing 
with the species emphasizes the absence of any parasites. Schmidt 
(SJf.) in Austria, and Kollar (&£, p. 108) in Germany, reared hyme- 
nopterous parasites from P. nubilalis larvae, but the species con- 
cerned and their status were not mentioned. Jablonowski {29) in 
Hungary reared a single individual of Masicera senilis Rond. from 
the larva, and two or three individuals of undetermined parasitic 
wasps from larvae and pupae. The same author found P. nubilalis 
eggs parasitized by a very small unknown hymenopteron, but it was 
not possible to estimate the economic importance of this parasite. 
The author also mentions in this connection that Oophthora sembli- 
dis Aur. is known as an egg parasite of many insects in Europe, and 
intimates that this may be the species concerned. Kostinsky recorded 
the rearing of parasites from P. nubilalis in Russia (Kiev) and 
Dobrodeiv (H) hi the Don Province of Russia, but their names or 
their importance are not mentioned. 
During 1919 the Bureau of Entomology established a laboratory 
in southern France for the purpose of investigating the parasitic 
