Eleventh Report of the State Entomologist 139 



Smith: List of Lepidop. Bor. Amer., i8gi, p. 77, no. 4053 (as Pyrausta 



fuiilalis). 

 Moffat: in Canad. EntomoL, xxvi, 1894, p. 126 (collected at London, 



Ont.). 



In the early part of July one may find here and there a leaf of the com- 

 mon spreading dogbane, Apocynnm androsiemifoliiim, more or less inclosed 

 with a shght web, and underneath a number of naked caterpillars with 

 greenish-yellow bodies marked with sooty-yellow spots and with a head 

 of a similar color to that of the tubercles. Later the web includes more 

 and more of the plant, until whole branches and even entire plants are 

 included. In the meantime the larvae have changed to a coppery red 

 with black tubercles, and the head has become heavily mottled with 

 black. Upon bringing larvae thus obtained to maturity, the moth of the 

 above-named insect was disclosed. 



The Eggs. 



None of the eggs of the insect were discovered before they had hatched, 

 but on the under surface of some of the leaves upon which the young 

 larvae were found, there were a few very delicate fragments of transparent 

 egg shells which were in all probability those of this insect. They were 

 deposited in a small mass, each nearly touching its neighbor; the number 

 in a group being about ten to fifteen. 



Habits of the Caterpillars. 

 The young larvae confine themselves to the under siuface of the leaf, 

 where they eat the lower epidermis and the soft parenchyma. Before at- 

 taining full size, the caterpillars moult four times at intervals of four to nine 

 days. They are gregarious and, as they eat and move about, a web is 

 spun which incloses their food and at the same time affords protection to 

 its inmates. The leaves thus skeletonized, quickly turn brown, become 

 dry, and the nest is soon a conspicuous object among the unharmed 

 foliage. As the caterpillars increase in size, they eat some holes 

 through the leaves, though most of the time they prefer the soft paren- 

 chyma and remove the epidermis from but one surface. Larvae which 

 were confined singly in cages and each given a spray of the dogbane to 

 feed on, were observed to spin a slight web to serve as a retreat and 

 usually one or more leaves were drawn together to make this retreat 

 more secure. The caterpillars complete their growth in about four weeks 

 during which time they eat most voraciously ; leaf after leaf is inclosed in 

 the web until not only branches but almost entire plants are devoured. 

 At Ithaca, N. Y., on August 10, 1895, whole masses of their food-plant 



