APANTELES MELANOSCELUS GIPSY-MOTH PAEASITE. 13 
recorded as a host of this parasite in Europe, was not found in 
America until the latter part of June, 1920, when a heavy infestation 
was discovered at Medford, Mass. When the infestation was found 
the larvae were from half to full grown and rather too large to be 
expected to harbor A. melanoscelus maggots. Collections of larvae 
| were made immediately, but no A. melanoscelus were reared. On 
several occasions, however, cocoons of this species were found on tree 
trunks closely associated with belated larvae of Stilpnotia salicis, and 
there is very little doubt that these cocoons were spun by A. mela- 
noscelus maggots which had issued from the near-by small and 
inactive larvae of S. solids. It is known that with the gipsy moth 
the larvae from which A. melanoscelus maggots issue do not die for 
several days. They are rather inactive and often do not move far 
from the place where they were when the parasite issued. 
|a In August, 1920, an outbreak of Hemerocampa leucostigma S. & A. 
™ was located in a small area in Somerville, Mass. This is the first 
time since A. melanbscelus has been established that larvae of the 
white-marked tussock moth could be collected in eastern Massachu- 
setts, except very sparingly. The season was too far advanced to 
expect to rear A. melanoscelus from collected material, and none were 
recovered from larvae brought to the laboratory. It was apparent, 
however, from observations made at the infestation, that this parasite 
had been responsible for the untimely death of very many tussock- 
moth larvae, for the cocoons of A. melanoscelus were abundant on 
the sheathing of near-by houses where the tussock-moth larvae had 
gathered in large numbers and were spinning their cocoons. 
Several experiments were tried confining adults of A. melanoscelus 
with various larvae. Reproduction was successful with Malacosoma 
' americana Fab., M. disstria Hiibn., Hemerocampa leucostigma S. & 
A., Olene basiflava Pack., and Euproctis chrysorrhoealj. The female 
attacked all but the last eagerly. Oviposition apparently took 
place in Charidryas nycteis D. & H., Hemileuca maia Dru., Pteronus 
ribesii Scop., and in a species of tortricid. All of these larvae died 
and were dissected. Several maggots of A. melanoscelus were found 
in the larvae of C. nycteis, but no evidence of parasitism was found in 
the other larvae. 
Several larvae of Stilpnotia salicis were presented to females of 
A. melanoscelus. No oviposition was recorded. This was late in the 
season and the larvae had matured much beyond an attractive stage 
for oviposition by this parasite. 
Some six or seven species of smooth-skinned or hairless larvae have 
been confined with females of A. melanoscelus but rarely have they 
shown any attention to them. This parasite evidently will attack 
quite a number of small hairy lepidopterous larvae when the oppor- 
73070°— 22 3 
