208 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 93 



38 to 40, irregularly biordinal and arranged in a complete circle. 

 No anal fork. 



PUPA 



Plate 23, Figures 7-9 

 Pupa small (5 to 6 mm.), moderately slender, tapering appreciably 

 from abdominal segments 7 to 10; caudal end rounded; cremaster 

 absent ; abdominal segments 3 to 7 each with a low, postmedian, trans- 

 verse, somewhat scalloped ridge on middorsum ; a transverse row of 

 fine, short spines near anterior margin on dorsum of each of abdominal 

 segments 4 to 8, and a girdle of short, rather well-spaced setae en- 

 circling the posterior margins of each of abdominal segments 4 to 7; 

 on each side and near the anterior end of the long slitlike anal open- 

 ing, a small, strongly sclerotized, flangelike projection, partially 

 covering a short, stout seta. 



At the time of writing many pupae are on hand. This is the stage in 

 which this species overwinters. The life cycle during the summer 

 is short (22 days), and from the data already gathered it seems 

 likely that there are at least two, possibly three or more, complete life 

 cycles annually. 



* The eggs are laid either on the leaves or flowers, the latter usually 

 being attacked first, and flowering trees definitely being preferred to 

 nonflowering ones. The larvae are at first gregarious, living together 

 in a heavy web spun throughout the affected parts of the plant. As the 

 larvae grow they spread out to various parts of the trees, tying the 

 leaves together in large, conspicuous masses. The leaflets, sometimes 

 little else being eaten, are then skeletonized, which causes them to die, 

 turn brown, and become detached at the rhachis. The leaflets may 

 remain on the tree, however, owing to the heavy webs by which they 

 are tied. 



When the larvae are full-fed they drop to the ground on long silken 

 threads. The threads are so numerous that one has (he sensation of 

 walking through spider webs when passing beneath an infested tree. 

 After dropping to the ground the larvae crawl to nearby objects and 

 spin cocoons in cracks and crevices, beneath the edges of the siding 

 of houses, on the bark of adjacent trees or, rarely, betwpen leaves of 

 the host plant. 



Note 



Since the above was written (Jan. L942) careful search in Virginia 

 has been made as far as 10 miles south of Petersburg and east to 

 Williamsburg. No evidence of the presence of the moth has been 

 found in Virginia. North of the District of Columbia, in Mont- 

 gomery County. Md., however, the species is much more abundant 

 and widespread than previously. Many trees in Takoma Park were 

 practically defoliated by the insect during the summer of 1942. 



J S. GOVERNMENT PRINTING OFFICE: 1943 



