136 SOME NOTES OX THE LIFE HISTORY 



free or in captivity ; the great difference between the two 

 states being in the mortality during the larval stages of life. 



During the earliest attempts at rearing the insects from 

 the eggs, a very high rate of mortality was found to be the 

 general rule. Egg bunches kept in a moist condition and 

 exposed to the sun by day failed to hatch out at all. Young 

 larvae similarly exposed to too great heat or moisture often 

 lost 80 or 90 per cent of their numbers in the course of 24 

 hours. ' Young larvae if left too near to water at night, were 

 frequently found with 50 per cent of their numbers drowned 

 the next morning. 



Consequently out of a great many egg bunches, which 

 hatched out an average of 30 to 40 larvae each, it was 

 frequently the case that no more than 5 or 6 per cent reached" 

 the stage of pupa. 



This very high rate of mortality was found to be, to a 

 considerable extent, avoidable with extra care, the eggs being 

 kept in well corked specimen tubes until they hatched out, the 

 very young larvae being kept completely isolated from ants, 

 with but little moisture, and plenty of shade. 



Yet even when better methods of preserving them were 

 practised, the mortality among young larvae was still, in most 

 cases, as high as 30 or 40 per cent, apparently from natural 

 causes, variations in weather, or in the quality of the food. 



There is a considerable mortality too during the changes 

 from larva to pupa, and from pupa to imago, in the free state 

 as well as when in captivity ; the following instances were 

 noted : — 



During the change from larva to :piipa : — 



Out of 20 larvae 4 died 



do. 



5 



do. 



3 



do. 



do. 



12 



do. 



1 



do. 



do. 



20 



do. 



2 



do. 



do. 



37 



do. 



1 



do. 



do. 



41 



do. 



1 



do. 



Average nearly 9 per cent. 



Jour. Straits Branch 



