BEETLES. 25 



The grubs (larvae) of the Lady-birds are much 

 the most voracious, and on that account are armed 

 with two very powerful jaws. They creep along 

 on the leaves and branches of plants until they find 

 plant-lice, among which they then ravage like wolves 

 in a sheep-fold. When full grown, their body is 

 generally half an inch long, of an oblong form and 

 blueish colour, with four or six yellow spots, which 

 generally become black spots upon the red wing-covers 

 of the perfect insect. They remain in the condition 

 of larvae about two weeks, when they fasten them- 

 selves upon a leaf, cast their skin, and rnetarnorpkose 

 themselves into a variegated or ash-coloured, short 

 cocoon, from which the perfect Lady-bird issues in 

 about a fortnight. 



A great variety of these insects are found through- 

 out the whole world, but the largest species we have in 

 North America is the Northern Lady-bird (Coccinella 

 Borealis, Fig. 5), which is principally found upon the 

 leaves of the Pumpkin vine, and several other species 

 of gourd (Cucurbitaceae). Here they feed in company 

 with their grubs, not on the leaves of any of these 

 plants, as many believe, but on the plant-lice and 

 the larvae of the Squash-bug which abounds on those 

 vines. 



Many other species of this genus, which are found 

 in this country, are named according to the number 



