gi6 



The Colorado Beetle. 



[FEB., 



currant, various thistles, goosefoot (Chenop odium hybridum), 

 thorough-wort (Eupatorium perjoliatum), and mullein. 



Grasses and other weeds have been known to harbour the 

 larva?. In some allotments at Tilbury Docks, where an 

 isolated colony of these beetles was found and destroyed in 

 1901, the larvae were observed feeding on woody nightshade 

 (Solatium Dulcamara), cabbage, and thistles, while the eggs 

 were found in one case on the sow-thistle (Sonchus). 



Destructive Character of the Insect. — Both the adults and 

 the larvae are destructive. The adult beetles destroy young 

 plants just coming through the soil, eating them, it may be, 

 to the ground. Beetles and grubs defoliate older plants. In 

 plants not altogether destroyed tubers may be produced, but 

 they may be small and are poor in quality. 



Description of Insect. — The adult beetle is about one-third 

 of an inch in width, and a little under half an inch in length. 

 In colour it is yellow, with five longitudinal black lines on 

 each wing-cover ; the head has a triangular black spot ; and 

 the thorax has dark spots and a more or less irregular V- 

 shaped mark in the middle. (See Fig. d.). 



The eggs are elongate-oval in form, and orange in colour. 

 They resemble those of some of the Lady-birds (Coccinellidce), 

 but are much larger than those of any of our native species. 

 (See Fig. a.). 



The young, soft-bodied larvae are of a dull red or red- 

 brown colour, and bear some resemblance to the larvae of 

 Lady-birds. As they grow they become paler in colour, 

 varying from a dull brickdust-red to an almost orange hue, 

 with the head, legs, and posterior part of the first segment 

 black. They also bear two rows of black tubercle-like spots 

 along each side, the upper row being the larger and composed 

 of seven spots. As the larvae mature the body becomes some- 

 what swollen and more or less arched, the apex terminating 

 in a kind of sucker, the upper part of the two apical segments 

 being black. The full-grown larvae are rather more than half 

 an inch long when extended. (See Fig. b.). 



The pupa is of the same red or orange-red colour as the 

 larva and bears black marks. (See Fig. c). 



Life History. — In the imago or beetle stage the insect 

 hibernates in the soil at a depth varying from a few inches 



