December, '09] JOURNAL OF ECONOMIC entomology 397 



The adults emerge during the night and if not disturbed will re- 

 main in the vicinity of the pupal cases throughout the following day. 

 Usually the males may be distinguished from the females not only by 

 their smaller size but also by two round black spots on the thorax 

 (Plate 17, B). Mating occurs shortly after emergence. The length 

 of tiine between emergence and egg deposition may be seen from the 

 following : — i I ! |" 



Days from emergence to ovipositiou. .. . 12 3 4 5 6 

 Number of females 12 2 4 11 



Thus on an average a female oviposits at the end of 3.45 days at the 

 room temperature of 70°F. Egg deposition may not, however, all 

 occur at once, as one moth may deposit several egg masses at different 

 times. The average life of an individual as seen from the following 

 is 14.6 days at 70°F : 



Length of life in days 11 12 13 14 15 17 20 



Number of moths 2 6 2 2 2 2 4 



Summarizing the life history it is found that at a constant tem- 

 perature of 80°F. the egg stage is 6.67 days, larva 32.69 days, pupa 

 6.41 days, and life of moth to oviposition 3 days, giving a total of 

 48.77 days or seven weeks. The difference in rate of development of 

 the eggs at 70°F. would indicate that the total life cycle at 70° would 

 require over ten weeks. This is about the temperature of a rose 

 house in this latitude in September. After October first the houses 

 have a mean of about 62°, running from 56° at night to 70 to 75° in 

 the day. With this temperature the life cycle would probably require 

 three to four months. 



Description 



Egg mass. (Plate 17, E.) Round or oval, flat, green patches, gen- 

 erally lighter green than the leaf ; laid very close together, frequently 

 overlapping; held together by glutinous material; average number in 

 mass, 117 ; varying in size from a small dot to one-fourth by one-half 

 inch. 



Larva. (Plate 17, F). Generally light green in color, varying in 

 some specimens to a reddish or brownish green ; a darker green stripe 

 generally evident along the dorso-mesal line; head round, very dark 

 brown or black mottled with, brown ; mouthparts lighter brown ; ante- 

 rior portion of clypeus light brown ; anteclypeus greenish white ; 

 labium green -with the exception of the distal portion and a black 

 triangular spot near the base ; labial palpi green, first and basal seg- 

 ment black; antenna of three segments; tip of antennae dark brown, 



