32 Journal of the Department of Agriculture. 



They were observed to live from 194 to 284 days, with an average of 

 230 days. Females, emerged in spring, lived up to 131 days, with an 

 average of 80 days. Males under observation lived up to 219 days, 

 with an average of 87 days. iNo males have been carried alive 

 through the M'inter; but it is considered tliat some also hibernate. 

 It must be borne in mind that the observations were made in Durban, 

 which has a comparatively hot climate, and that the periods may be 

 more protracted where the climate is cooler. It is quite probable that 

 the life-history on our high veld is considerably longer. 



Females were found to lay their last eggs from one to nine days 

 before dying. Except in the case of those which emerged late in 

 the season and hibernated before egg-laying, the females usually 

 started to lay from the fourth to the seventh day after emerging; 

 but in some cases the first eggs were laid from the eighth to the 

 fourteenth day. 



Beetles copulate before any -food has been taken, often on the 

 hrst day after emerging, but, apparently, no eggs are laid before 

 the female has fed. Unmated females may lay eggs. Their eggs are 

 fewer in number and laid more scattered, and more single eggs are 

 laid. No unfertilized eggs have been found to hatcli. A female 

 which laid only unfertile eggs after hibernation, was put with a 

 male six months after emerging, and was then fertilized. Fertile 

 females may hibernate and then, without having mated again, lay 

 eggs which will hatch. This is of some importance, as it shows it is- 

 possible that hibernating females may set up new centres of infesta- 

 tion. 



When hibernating, the beetles may rest for months on the same 

 spot, and in cold situations they probably remain in one place all 

 the time; but in Durban they have been observed to move about 

 occasionally, although not to feed, even when placed on their food- 

 plant. They must feed first to be able to hibernate. Beetles emerging 

 late in the season, when others were already hibernating, died after 

 two to four days when not supplied with food, while those which were 

 fed hibernated successfully. 



The kind of situation chosen by the beetles as hidings-places for 

 the winter is indicated by Mr. David Gunn, of tlie Division, in these 

 words : — 



"When at Bathurst District a few days ago (June, 1920), I 

 visited the farm where I had found L. bilineafa last summer, and was. 

 informed by the owner that the insect was hibernating in thousands, 

 in his cupboards, wardrobes, clothes, m bedrooms, and in every tivail- 

 able place where warmth could be obtained. I Avaj able to confirm 

 his statements." 



At Piet Retief hibernating beetles were found iinder stones and: 

 in the sheds amongst both loose and baled tobacco. 



When handled, the beetles give off a rather offensive odour. 

 Sometimes they make a cheeping noise. They can fly well, but,, 

 when disturbed, they usually drop to the ground and often feign 

 death. Occasionally, however, they at once take flight. In the 

 early morning and on dull days they are more sluggish, and are 

 then more easily collected. The males aie more active than the 

 females. 



Number of Gemoeations. 



In Durban the possible maximum number of generations in the 

 year appears to be eight; but the average number from one 



