204 



BEETLE PESTS< 



In general the presence of these insects may be disregarded unless 

 they come in extraordinary numbers or are infesting small plots of valu- 

 able experimental crops. No treatment will affect the larvae if they are 

 in the plants. Spraying with lead arseniate poisons the beetles ; Bor- 

 deaux mixture is a specific for these beetles when properly prepared 

 and sprayed on the plants. The bag is a useful mechanical method on 

 wheat or rice and its effect is enhanced by oiling the inside of the bag 

 with kerosene or heavy oil. 



FIG. 240. 



Epilachna Beetle. 



On the right the antenna, on 



the left the leg. 



Bpilachna Beetles. 



Oil brinjal (Solanum melongend), turia (Liiffa acutangula)j dudhi 

 (Lagenaria vulgarix) and other cucurbitaceous 

 plants, and on many wild plants, one finds 

 small round beetles shaped like a half pea, of 



Iw\^^^^m^^^\ a ^ u ^ re< ^ c l ur w ^ black spots. They feed 

 rf II?* MBi *^M u P n the leaves, taking a series of bites off the 



epidermis and producing a very characteristic 

 stippled appearance : with them are often their 

 larvae) small oval grubs, yellow and very spiny. 

 These beetles belong to the true lady-bird 

 beetles which normally eat plant-lice, mealy 

 bugs and scale insects ; the epilachnas alone 

 are herbivorous both as larva and imago. 

 The life history is similar to that of the rest of the family ; the eggs 

 are cigar-shaped, yellow, laid in clusters, each egg on end side by side. 

 Mr. Haymann found that one beetle laid 280 eggs. 



The eggs hatch in about five days, the young feeding at once upon the 

 epidermis of the leaf. When full grown the larvae are one-quarter of an 

 inch long, flattened and oval covered with short spines. They cling tightly 

 to the leaf and move slowly. They live from three to four weeks, and 

 pupate on the leaf, the pupa being attached by the tail. The larval skin 

 is not completely thrown off j after four to six days the imago emerges. 



These insects are most abundant from July to November, there 

 being several broods during that time. The beetles live through the 

 cold weather and emerge about March, when they often couple and lay 

 eggs if a food-plant is available. 



As in all beetles of this family, they can live for long periods until 

 fresh food is available. They are injurious simply by destroying the 

 leaves, and under favourable circumstances become abundant. Garden 

 crops are injured, field crops practically never. In gardens the simplest 



