DIASPINJ4. 



69 



DlASPINJil. 



Insects covering themselves with a dorsal and ventral 

 shield or scale (puparium), composed partly of discarded 

 skins and partly of secreted matter, or entirely of dis- 

 carded skins (exuviae). Females apodous after the first 

 stage, have rudimentary antennae and monomer ous 

 mentum. 



PUPAEIUM OF FEMALE. 



This is formed by the three stages of the insect, 

 viz. larva, second-stage female, and the adult. In the 

 larval stage the dorsum usually becomes covered with 

 secretionary matter, varying from a very delicate 

 transparent film to an opaque nipple- shaped structure ; 

 and towards moulting period the upper parts of the 

 derm become highly chitinised. Mr. Green* has ob- 



FIG. 1. 



FIG. 2. 



FIG. 1. Larval exuviae of Aspidiotus. x 30. 

 FIG. 2. Larval exuviae of Mytilaspis. X 30. 



served a remarkable difference in the method of 

 effecting the ecdysis between Aspidiotus and other 

 genera. He says, " In Aspidiotus the larval skin splits 

 along the margins, completely separating the dorsal 

 and ventral halves, which subsequently become incor- 

 porated respectively into the dorsal and ventral scales 

 of the puparium. In this case the visible part of the 

 pellicle will be destitute of the sheaths of the antennae 



* Coccidee of Ceylon, p. 24. 



