SUBFAMILY MARGARODINAE 91 



sented by ringed disks bearing one or two curved setae. There is 

 some disagreement as to the disappearance of the rostrum and 

 rostralis. Giard maintains that they exist and are functional in 

 all the nymphal stages but are small and inconspicuous and that 

 they are not lost until the assumption of the adult condition. 

 The later observations of Green would seem to confirm this conten- 

 tion of Giard. 



Green has figured and described a stage of niger, which was 

 obtained from small scales, which differs from all of the stages 

 previously described. It is oval in outline and lacks legs. The 

 antennae are represented by small tubercles with a pit bearing two 

 curved setae. The mouth-parts are well developed. The abdo- 

 men bears seven pairs of spiracles instead of eight as in the adult. 

 The sterna of the abdominal segments bear five longitudinal rows 

 of small circular glandular pits or cerores. A still earlier stage 

 was observed. These may represent stages in the development of 

 the male which is unknown. 



The female Margarodes may remain apparently for a consid- 

 erable time, several years, within their cyst if the conditions for 

 their emergence are unfavorable. She eventually breaks through 

 the wall of the scale and emerges as an insect that is normal in 

 form at least for a coccid. The body is globular. The antennae 

 are short, gradually tapering toward the distal end, varying with 

 the species from seven to nine segments. The mouth-parts, including 

 the rostrum and rostralis, are wanting. The prothoracic legs are 

 greatly enlarged, the profemora are thickened and fitted for dig- 

 ging. The other two pairs of legs are normal in form. The body 

 may be shaggy with fine short setae or nearly glabrous. The 

 dorsal and ventral aspects may bear short conical spines, the 

 dermal spines of Green. The lateral margins of the body and the 

 dorsal and ventral aspects may bear transverse groups of cerores 

 with intermixed setae. The body becomes more or less covered 

 with a white mealy or powdery wax or a loose woolly wax. The 

 thoracic spiracles and those of the first abdominal segment open on 

 the ventral aspect, while the remaining abdominal spiracles open 

 on the dorsal aspect or on the lateral aspect as in mediterraneus. 

 The thoracic spiracles are much larger than the abdominal. There 

 are cerores usually associated with both the thoracic and the 

 abdominal spiracles. The anus and vulva are located on the 

 ventral aspect. The former is small and surrounded by a 

 chitinous plate. The adult females vary greatly in size. Green 

 reports in the case of papillosus a variation of 1.14 mm. to 4 mm. 



