SCALE INSECTS OF IMPORTANCE 365 



FIG. 



e, e^ e, e^ <f, e^ <?, e chitinous processes, or thickened margins of incisions 



/ general thickening inward of body wall 



Si Si S ventral grouped glands, or spinnerets 



h ventral chitinous thickening 



/ vagina 



k, k transverse chitinous thickenings of dorsal wall 



/, /, /, / dorsal pores, showing different appearances seen in focusing 



w, m wax ducts, within body 



n anus 

 2 Aspidiotus ancylus Putnam, adult female. Note fringing 

 plates, the single pair of lobes, and the linear arrangement of 

 ventral glands. Compare with A. ostreaeformis, plate 14. 



PLATE 12 



FIG. 



1 Aspidiotus forbesi Johnson, adult female. Note chitinous 



thickenings and form of lobes. Compare with figure 2. 



2 Aspidiotus perniciosus Comstock, adult female. Ventral 



glands are absent. Note plates. 



PLATE 13 



FIG. 



1 Aspidiotus forbesi Johnson, second stage. Compare with 



adult, plate 12, figure i, and with A. perniciosus, second 

 stage, on plate with it. 



2 Aspidiotus perniciosus Comstock, second stage. Com- 



pare with adult, plate 12, figure 2. 



PLATE 14 

 Aspidiotus ostreaeformis Curtis, adult female. Note form 

 of second lobes and grouping of ventral glands. Compare with 

 A. ancylus, plate 11, figure 2, and with the other species figured. 



PLATE 15 



FIG. 



I. Aspidiotus ancylus Putnam, second stage. Note plates in 

 comparison with A. ostreaeformis at figure 2. Compare 

 also with adult, plate 11, figure 2. 



2 Aspidiotus ostreaeformis Curtis, second stage. Com- 

 pare with adult, plate 14. 



