614: TROCEEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 



former may easily be distinguislied from the eggs, nymphs and adults 

 of the latter by the following prominent characteristics : — 



Pseudococcits vir gains, Ckll. 

 Egg, pale yellow, ovoid ; nymph, pale yellow with a pair of whitish 

 caudal setse ; female stout, thinly covered with white meal, 

 with a pair of whitish setse at caudal «nd, the lateral margins 

 as well as the venter covered with small, white hairs, especially 

 so when gravid and about to lay eggs. 



Phenacoccus hirsutus, Green. 

 Egg, cylindrical, bright pink with one end sufEused with bright pink; 

 nymph, bright pink, thinly covered dorsally with a thin 

 whitish meal (in some cases when attended by ants the meal 

 wears of?) ; adult female bright deep pink with a light fuscus 

 tinge, ovisac of whitish felted threads which envelop the 

 female entirely. The eggs are laid touching each other within 

 the cretaceous white ovisac. 

 Besides these, the presence of the nymphs and adult females of 

 Pseudococcus virgatus does not cause the crumpling of the apical leaves 

 and the subsequent malformation of the apical heads. In a series of 

 experiments conducted with the nymphs of Pseudococcus virgatus, along 

 with those of Phenacoccus hirsutus, to find the malformation of leaves 

 and shoots caused by the two mealy-bug«, it was found that in one or 

 two instances there was a slight crumpling of the leaves caused b}'" P. 

 virgatus, but it was not so striking as the curling of the leaves caused by 

 Phenacoccus hirsutus within the same length of time. If, however, 

 the nymphs and fema'es of P. virgatus strayed over and got mixed with 

 the nymphs and adult females of P. hirsutus, they could be separated 

 easily by their colour differences as well as by the presence of caudal 

 setae. The case was, however, different when P. hirsutus occurred on 

 cotton along with P. corymhatus and P. virgatus. In such a case as this 

 there was no difficulty in first separating P. hirsutus from P. virgatus, 

 and then dift'erentiating between P. hirsutus and P. corymhatus. To do 

 this satisfactorily some experience is however necessary. The two mealy- 

 bugs may, however, be distinguished on the plants by means of the 

 following superficiul t^\aracteristics. To do the differentiation critically, 

 the specimens must first go through the usual mounting technique and 

 then an examination of their pygidial ends will give characters suffi- 

 ciently distinct. The eggs of P. hirsutus lie loosely within the female 

 ovisac and are bright pink in colour with one end suffused with scarlet. 

 The female is bright pnik Vv^ith an ovisac consisting of white, cottony 



