THE SOUTHERN BEET WEBWOEM. 



19 



the larvae had pupated and by May 20 the adults had commenced 

 to issue, thus giving a total period for the pupal stage of about 12 

 days. The moths were placed in a large cage with a growing beet 

 and at the end of the week all had died. 



In other sendings of material the moths were observed to issue on 

 May 25, June 3, and July 9. 



The length of the egg stage was not ascertained, but it may be 

 safely stated to be approximately 6 or 7 days, in moderate or 'warm 

 weather. From eggs laid on June 5 and 6 the adults developed July 

 3, gi T ring a total life cycle of 28 days, or 4 weeks, in hot weather, 

 which will be about the minimum for the species. . Assuming that 



Fig. 3.— Southern beet webworm (Pachyzancla bipunctalis): a, Moth; b, larva; c, lateral view of first 

 proleg and abdominal segment of larva; d, pupa, with cremaster showing location of hooks at right. 

 ( b, d, About three times natural size. (Original.) 



from 5 to 7 days is occupied by the egg stage, and approximately 

 the same number of days for the pupal period in hot weather, the 

 larval period would be approximately from 14 to 18 days. At least 

 four generations are indicated for this species, and it is possible that 

 there are more, but there are no positive data on record on this point. 



DESCRIPTIVE. 



The moth. — The moth in color varies from buff to very pale yellow- 

 ish gray. The wings are slender and the antennae long. In the pale 

 forms the wings are nearly transparent, and the surface is rather 

 iridescent purplish. The wing pattern of the pale individuals is faint, 

 much more so than the illustration (fig. 3, a) would appear to indicate, 



