INSECT ENEMIES OF EASTERN FORESTS 349 
horny tubercles, of which those on the second thoracic segment, and 
also sometimes those on the third, are rather long and curved. 
The free-feeding naked larvae include the sphinx caterpillars or 
hornworms of the family Sphingidae, which have either a horn or an 
eyelike tubercle on the eighth abdominal segment; the loopers, meas- 
uring worms, cankerworms, or geometers of the family Geometridae, 
so-called because of their manner of locomotion; the cutworms of the 
family Phalaenidae, and others. ; 
The bark and wood-boring larvae infest the trunk and larger 
branches and roots of trees, and in some cases the food plant aids in 
the identification of the species. These insects belong to families 
Aegeridae, Cossidae, Phycitidae, Hepialidae, and others. 
The bud, shoot, and twig borers belong to the families Tortricidae, 
Phycitidae, Olethreutidae, and Nepticulidae. The leaf-stem borers 
are found in the Nepticulidae, Lavernidae, Tortricidae, and Oleuthreu- 
tidae. The fruit, nut, cone, and seed borers are members of the fami- 
hes Tortricidae, Blastobasidae, Phycitidae, and others. 
At least six famihes (Incurvariidae, Psychidae, Gelechiidae, Ama- 
tidae, Arctiidae, and Zygaenidae) are represented by one or more 
species whose larvae feed on lichens on trees or rocks. Among these 
species are found casebearers, bagworms, and hairy, and naked larvae. 
Occasionally some are more or less common locally. The larvae of 
several species in the family Tineidae, particularly in the genera 
Scardia and Tinea, are external feeders or borers in fungus 
growths, and many are scavengers. They are generally casebearers. 
The moths are small, most species having a wing expanse of less than 
1 inch. 
PARASITIC AND PREDACEOUS HABITS 
In the United States there is only one species in the Lepidoptera 
which is known to be an internal parasite, and very few species are 
truly carnivorous in their habits. Two widely distributed species, 
whose habits have been studied, are mentioned here because they both 
attack important forest insect pests. 
The larva of Huclemensia bassettella (Clem.) (family Heliodini- 
dae) is an internal parasite of the oak soft scale, Hermes sp. It isa 
stout larva with a brown head and white body. The moth has a wing 
expanse of about 8% inch and is active in July and August. It ranges 
from Ontario to Texas. 
The larva of the butterfly Peniseca tarquinius (¥.) (family Lycae- 
nidae) feeds on woolly aphids. It is found most often in colonies of 
the woolly alder aphid (Prociphilus tessellatus (Fitch) ). When fully 
grown it 1s about 5 inch in length. The head is brown, the body slug- 
like and clothed with short black-and-white bristles. The larva is 
usually well concealed as the white exudations of the host adhere to 
the bristles on the body of the larva. The winter is passed as a chrysa- 
lis, and the adult of the first brood emerges late in May. There may 
be two or three generations a year, and larvae are found until early 
in October. 3 
Because of the large number of Lepidoptera which may from time to 
time be found in considerable abundance in the eastern part of the 
United States, it is practically impossible to construct a key to the 
larvae of all the common species by using nontechnical terminology. 
