18 BULLETIN" 1469, U. S. DEPARTMENT OF AGRICULTURE 
contain 1, and 1 to contain 2, second-stage maggots; and 1 larva 
was parasitized by 1 second-stage and 3 first-stage maggots. 
In connection with the gipsy -moth work large collections of gipsy- 
moth caterpillars have been made each year, from which Compsilura 
have been obtained for colonization. There have been few heavy 
gipsy-moth infestations in and around Melrose in recent years, and 
as the satin moth is an attractive host for Compsilura large numbers 
of satin-moth caterpillars have been collected from which Comp- 
silura for colonization were obtained. The favorable food plants 
of the satin moth are often planted in groups, and as only poplar 
and willow trees have been affected it has been possible to' make 
collections of larvae very rapidly from a heavily infested locality. 
Besides the records obtained pertaining to Compsilura concinnata, 
Calosoma sycophanta, and Blepharipa scutellata, field observations 
have strongly indicated that another one of the introduced and estab- 
lished gipsy-moth larval parasites, Apanteles melanoscelus Ratz., 
attacks satin-moth larvae in the field. 9 
Another species, Apanteles vitripennis Hal., a very common braco- 
nid parasite of gipsy-moth larvae in Europe, has been colonized in 
New England in the last two years. It is not as yet positively 
established, although since colonization it has passed through a gen- 
eration in the field. In laboratory experiments it attacks small 
satin-moth larvae. It apparently needs a host in which to hibernate, 
and several unsuccessful attempts have been made to induce it to 
hibernate in small satin-moth larvae. It has not been conclusively 
shown, however, that A. vitripennis can not under field conditions 
pass the winter within hibernating satin-moth larvae. In the spring 
of 1925 a few hibernating satin-moth larvae were collected at North 
Hampton, N. H., where a colony of A. vitripennis was liberated in 
1924. Several of these larvae were dissected by C. F. W. Muesebeck, 
of the Gipsy Moth Laboratory, and in one of the caterpillars a hiber- 
nating Apanteles larva was found. It was not possible to determine 
the species of this braconid and no parasites were reared from the 
remaining larvae of the collection. 
A parasite of the gipsy-moth egg, Schedius kuvanae How., intro- 
duced from Japan, attacks readily and successfully the satin-moth 
eggs when they are exposed to it in laboratory experiments, and 
may under favorable conditions attack them in the field. 
Rather limited observations have been made to determine the de- 
gree of mortality of hibernating satin-moth larvae in New England ; 
up to the summer of 1925 it seemed to be slight. Examination of 
the hibernating larvae in several localities in the spring of 1926 
showed 45 per cent larval mortality. A mortality of 2.6 per cent 
may be attributed to a fungus associated with a few of the dead 
larvae, and a mortality of 20.7 per cent appeared to have been 
brought about by a small pteromalid. Maggots of this parasite were 
found feeding externally on the satin-moth larvae in hibernation 
webs. On examination of pieces of bark heavily infested with hiber- 
nating satin-moth larvae, many of the caterpillars in small areas 
on the bark were found to be dead, and apparently flattened, as 
9 Crossman, S. S. apanteles melanoscelus, an imported parasite of the gipsy 
MOTH. U. S. Dept. Agr. Bui. 1028. 25 pp., illus. 1922. 
