366 REPORT OF THE COMMISSIONERS OF 



The recently emerged caterpillar has been described as pale yellow, sparsely 

 haired, with a black head and with two rows of black marks along the body, but 

 as there is considerable variation in the color of the larva later in life, it would not 

 be surprising to find the same more or less true of its earlier stages. The hairy, 

 yellowish, brown and black marked caterpillars vary considerably in appearance. A 

 half grown and two full grown larvae are represented on plate 2, figure 2, a dorsal 

 and a lateral view being given of the latter two. The head is black and the whitish 

 or brownish hairs spring in clusters from the black and orange tubercles. 



The oval cocoon is thin and mixed with larval hairs or, where it is spun at or just 

 below the surface of the ground, particles of soil may be entangled in its meshes. 

 The brownish pupa may be recognized by the swelling near its middle (Plate 2, 

 figures 3, 4). 



The moth is very variable in appearance and ranges from a pure white to a form 

 much spotted with black. Compare figures 5 and 6 on plate 2. 



Identity of the insect. The extreme variability of the adult has led to the 

 bestowal of a number of scientific names on the insect which in its larval state makes 

 the conspicuous webs above described. There is even now a discussion in progress 

 between systematists as to whether all these webs are made by the larvae of one 

 species or not. For the present we will call the insect so abundant in New York 

 state the fall web worm and treat of it under the scientific name given above. 



Life history. The moths fly from early in June till the middle of August, at 

 least, occurring in large numbers in the middle of June, the early part of July and 

 the first half of August, according to captures by Dr H. G. Dyar at Poughkeepsie, 

 N. Y. Records kindly placed at my disposal by Prof. G. H. Hudson of the Normal 

 School at Plattsburgh, show that moths appear in small numbers at that place from 

 the 9th to the last of May, that they are quite abundant throughout June, being 

 most numerous from the 8th to the 10th and from the 14th to the 30th. They were 

 also present in small numbers throughout July, occurring in larger numbers on the 

 3d and 4th, and one individual was taken August 2. The caterpillars begin to be 

 noticed the latter part of June or early in July and are most abundant in August. 

 They were observed at Annandale, Dutchess county, June 27, 1900 and at Buffalo, 

 Erie county, July 3 in the same year. Thus in the southern portions of the state 

 the normal occurrence of at least a partial second brood can hardly be questioned 

 but so far north as Plattsburgh, it would appear from the record given by Prof. 

 'Hudson that but one generation a year is usually the rule. 



The eggs are deposited in clusters of several hundred on the underside of a leaf and 

 they hatch in warm weather in from seven to ten days, the young caterpillars begin- 



