166 NEW YORK STATE MUSEUM 



several shades of gray and grayish white. On the other hand, the 

 female is a nearly uniform gray, with simple antennae, and but rudi- 

 mentary wings. 



The eggs are deposited on the empty cocoon under conspicuous white 

 masses of froth (fig. i, //, k), which soon hardens and forms a very effec- 

 tive protection. The individual egg is nearly spherical, about -^ mm 

 in diameter, white or yellowish white, and with a light brown spot sur- 

 rounded by a ring of the same color. 



Life history. The winter is passed in the egg, the young emerging 

 about the latter part of May in this latitude. In his studies of this 

 insect, Dr Riley observed that the larvae molted seven days after hatch- 

 ing, and thereafter every six days till mature, males being produced 

 from those that passed through but four stages and females from those 

 exhibiting five or six. The rearings by Dr Dyar, indicate that the males 

 have six stages and the females six or seven. The growth of the caterpillars 

 occupies a month or a little more, pupation occurring the latter part of 

 June and early in July. In Albany most of the larvae had pupated by 

 July 7 of the present year, and some recently deposited egg masses were 

 to be seen. In New York city the eggs began to hatch May 25, 1883, 

 and the larvae to pupate about June 21, according to Clarkson (see cita- 

 tion). A few individuals spin up earlier than the mass and some do not 

 till numerous egg clusters indicate that most have already completed 

 the round of life. 



From 10 to 15 days are passed in the pupa state. At the end of this 

 period, the wingless female emerges and crawls upon her cocoon, pairing 

 takes place, and immediately afterwards deposition of the eggs begins, 

 as stated by Dr Howard. They are laid in a mass as described above, 

 the eggs of a cluster ranging in number from 100 to 500, as given by 

 several writers. In what appeared to be a good sized mass collected in 

 Albany, there were 330 eggs. After her full complement has been dis- 

 charged, the female dies and usually drops to the ground. In Albany 

 there is normally one annual generation, but in New York city and 

 vicinity and in Boston, Mass., there are two broods, while at Washington, 

 D. C, there are two and probably three broods each year, according to 

 Dr Howard. 



i^HabitS of the species. The young larvae feed upon the under sur- 

 face of the foliage, and as they increase in size more and more holes are 

 eaten, till, when full grown, all but the main ribs of the leaves are 

 devoured. A peculiar habit, recorded by Dr Lintner but not observed 



