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NEW YORK STATE MUSEUM 



scale begins, even before the young has selected its feeding place, as 

 very minute, white,' waxy filaments, which spring from all parts of the 

 body, rapidly become thicker and slowly mat down to form the circular, 

 white scale with a depressed ring and central elevation (pi. 3, fig. 5). 

 This white scale gradually becomes darker, and in a few days it has 

 assumed a black or dark gray color, with one or more lighter rings, as repre- 

 sented in plate 3, figure 13. The skin is cast for the first time 12 days after 

 the young appear. The molt, as is true of all species ofAspidiotus, 

 consists of a splitting of the old skin around the outer edge of the flat- 

 tened insect, the upper part being attached to the scale and the lower 

 portion forming a ventral scale next the bark. Prior to this molt the 

 sexes are indistinguishable, and both lose legs and antennae at this time. 

 The males may now be recognized by the large purple eyes and the elon- 

 gate, pyriform body, while the females are eyeless, and are practically flat- 

 tened sacs with only the slender, central sucking bristle. Six days later, 

 or when the insect is 18 days old, the male molts to the pro-pupa (fig. b), 

 and the male scale becomes an elongated oval in form. The antennae, 



Fig. 4 Development of male insect, d ventral view of young after first molt, b same after second 

 molt (pro-pupa stage), c and d, ventral and dorsal views of true pupa. (After Howard U. S. dep't 

 agric. div. ent. Bui. 3, n. s. 1896) 



legs and wings now appear in a very rudimentary condition and in two 

 days become much better shaped, when the change to the true pupa (fig. 

 c, d) takes place. Four to six days later, or from 24 to 26 days from 

 birth, the mature, two-winged males back out from under their protecting 

 scales. The female undergoes a second molt about 8 days after the first, 

 or when she is about 20 days old, and 10 days later she is full-grown and 

 within her transparent b(|fiy (pi. 3, fig. 10) are seen partly developed 

 young, which begin to appear in from three to 10 days later. Thus the 

 round of life may be completed, as determined from a study of the 



