THE SWEET-POTATO LEAF-FOLDER. 5 
Measurements of the wing expanse of 11 reared females gave an average of 
27 mm., ranging from 25 mm. to 29 mm. The wing expanse of 7 reared males 
ranged from 25 mm. to 27 mm. 
FOOD PLANTS. 
In addition to the sweet potato as a food plant, moths have been 
reared from larvae found feeding on uncultivated plants of the genus 
Ipomoea, to which the sw T eet potato belongs. It seems probable that 
some species of this genus, known under the common names of " bind- 
weed," "wild sweet potato," and " wild morning-glor} 7 ," are the 
natural larval food plants, and that the larvse will feed on any of 
the numerous species of Ipomqea, in which genus are included a num- 
ber of ornamental vines. | 
SEASONAL HISTORY AND HABITS. 
OVIPOSITION. 
Eggs have not been observed in the field at Baton Eouge, but the 
females, after feeding from pieces of sponge moistened in sweetened 
w r ater, oviposited freely on sweet-potato plants in cages. 
The eggs, which are securely ^fastened to the leaf, were placed on 
the underside, the areas aldngsidff' tne leaf veins being a favorite 
location; Mr. High, however, from observations made in Texas, noted 
that apparently the eggs are deposited indiscriminately on either side 
of the leaf. Eggs lOef sometimes placed singly but as many as five 
have been noted in a group, their edges overlapping, although in no 
regular arrangement. 
INCUBATION. 
Eggs laid in the insectary at Baton Rouge on July 29 and 30 
hatched on August 2 and 3", respectively. The period of incubation 
was, therefore, under these conditions, four days. The averages of 
the daily maximum and minimum temperatures for the insectary 
from July 29 to August 3, inclusive, were 92.5° and 74.0° F. 
HABITS OF THE LARVA. 
In the field the larvse are found between separate leaves or portions 
of the same leaf which have been fastened together to form " shel- 
ters," each of which usually protects one larva. The larva constructs 
its shelter by spinning threads of silk from side to side across a por- 
tion of a leaf near the edge, each strand being shortened as the pre- 
ceding strands contract in drying, until finally the edge of the leaf is 
