138 , TENTH ANNUAL REPORT OF 



After this general view, the lecturerer dwelt specifically on several 

 points ; and, first, on the Transformations of Insects. Everybody would 

 be suri)rised to see a bird of gorgeous plumage rise out of the earth, 

 proceeding from a serpent-like worm that had buried itself and re- 

 mained under ground for several years. This would be an extraordi- 

 nary metamorphosis, and yet the equivalent of this is occurring every 

 day during the summer. The butterfly, which sports in the air, and 

 sips nectar from every flower, was nothing once but a crawling cater- 

 pillar, which, entombing itself in the coffin or cocoon of its own con- 

 struction, or changing into a chrysalis, came forth at last the beautiful 

 animal you now behold it, with its habits^ food, appearance, organs, 

 entirely changed. And the same is true of nearly all insects. 



The different states of insects were now spoken of: the egg, larva 

 or grub, chrysalis and imago, or perfect insect, and the peculiarities of 

 each dwelt upon. The different modes of transformation were men- 

 tioned, and some of them were illustrated in full. Many curious and 

 striking facts in connexion with this head were introduced. The 

 habits of the ichneumon flies, which lay their eggs in caterpillars, by 

 inserting their ovipositors through their flesh, the larvee of which feed 

 on the fatty juices of the living caterpillar, and undergo their trans- 

 formation in the body^ and eat their way out as the perfect insect. 



The benefits and uses of insects were then exhibited. They are nature's 

 scavengers ; the carcases of animals are speedily consumed by the 

 larvas of various beetles and flies, and there is good ground for Linne's 

 assertion that three flies of a certain species will devour a dead hor^ 

 as quickly as a lion. Each will produce 20,000 grubs, which, in 

 twenty-four hours, will devour so much food as to increase their bulk 

 two hundred fold. The burying beetle inhumes small dead animals, 

 and ants perform no mean office in this respect. Putrescent vegeta- 

 bles and decomposing fungi are consumed by beetles, and stagnant 

 waters are purified by innumerable larvas. Noxious insects are kept 

 within proper* limits by others ; wasps destroy multitudes of spiders 

 and grasshoppers, and the family of ichneumon insects kill thousands 

 of caterpillars. If it were not for the larva? of the lady-bird, so com- 

 mon in our gardens, our roses, and some other flowers, would be de- 

 stroyed by the parasitic animals upon them. The singular ant-lion, 

 which lies in wait for its prey in a hole in the sand, and most curiously 

 throtos stones at its retreating game, destroys many noxious insects. 

 Nothing escapes the ruthless attacks of the ichneumons ; they assault 

 the spider in his web, the bee in his retreat ; they find out the larvsB 

 of the Hessian fly and kill millions of them. The tiger-beetle preys 

 on the whole insect race, and the water-beetles are no less cruel on 

 their congeners. Ants, wasps, hornets, dragon-flies, in a word nearly 

 all are employed by Providence in keeping down a superabundance of 

 these little animals, which, if left unmolested, would be a plague on 

 the earth. Insects are real cannibals ; even some species of caterpil- 

 lars will devour each other. Some devour their own offspring with 

 savage ferocity, and the young of the mantis will fall on and devour 

 each other as soon as they are excluded from the egg. 



Insects, wholly or in part, constitute the food of some of our most 

 esteemed fishes and birds ; they aff'ord nourishment to some quadru- 



