THE SADDLED PROMINENT. 325 



previous season to secure pupae and was surprised to find the 

 moths already emerging in great numbers in the woods. Sev- 

 eral hours were spent collecting pupae, an easy matter in this 

 thickly infested region. Many moths emerged on the way to 

 Orono but enough pupae were secured for ample material for 

 the life history cycle. 



May 29. Moths deposited eggs upon the beech leaves with 

 which their cages were supplied. 



June 7. First instar. Larvae began hatching and in great 

 numbers. 



June 11-12, Beginning of second instar. The larvae spin- 

 ning their molting mats on the cage and leaves June n and 

 molting during the night. 



June 16-17. Beginning of third instar. The mats being 

 formed June 16, and the molt occurring during the night and 

 June 17. 



June 23-24. Beginning of fourth instar. 



June 30- July 2. Beginning of fifth instar. Last stage. 



July 13. The first larvae observed to be forming pupal cells 

 in the earth provided for them. These pupated promptly. 



October 7 the date on which this bulletin goes to press, no 

 moths have emerged from these pupae though the pupae are 

 alive as evidenced by their vigorous movements on being dis- 

 turbed. The pupae were kept in the insectary under leaf mold 

 where the temperature does not vary appreciably from that out 

 of doors. 



This record should settle the question of a double brood for 

 Maine. If moths emerging so early as May with the succeeding 

 larvae full fed in mid July do not give two generations (and the 

 summer was particularly warm and dry) there would seem to 

 be no possible chance for two broods in this latitude. 



That this species is very susceptible to temperature control 

 is evidenced by the fact last winter that from pupae which were 

 wet and warmed in the laboratory moths emerged December 3, 

 1907.* 



Individuals hibernating in a place which did not warm up 

 early in the spring might easily be a month or so later in emerg- 

 ing which would give late larvae and conversely exceedingly 

 early individuals to emerge in the spring might perhaps make 



* Me. Agr. Exp. Sta. Bui. No. 148, 1907. 



