Fereday. — On the Injuries to Vegetation hy Insects. 293 



intimately connected witli the things they destroy, that we cannot effectually 

 apply any direct remedy, without at the same time destroying or injiiring what 

 we attempt to preserve. It is an error to suppose that caterpillars, or the 

 larvae of insects, are -to any considerable extent affected by atmospheric forces. 

 The severest frost does not destroy their vitality, for if they fail to find a 

 sufficient shelter torpidity only is produced. I have myself taken caterpillars 

 from the snow so entirely frozen as to have become brittle as glass, and yet, 

 when exposed to the warmth, they have quickly revived and resumed their 

 activity, without having suffered any apparent injury. When inundations or 

 heavy falls of rain take place, and' the ground becomes completely covered 

 with water for days or weeks, considerable mortality is probably caused 

 amongst the caterpillars ; but such occurrences are only occasional and local. 



Our only remedy is an indirect one, and that I conceive to be the employ- 

 ment of insectivorous animals to do the work for ns ; and for this purpose 

 insectivorous birds stand prominent. I consider it to be our duty not only to 

 protect the few indigenous birds that yet remain, but to continue to introduce 

 others, until we have restored the balance which has been disturbed. 



Of indigenous insectivorous and insect-destroying animals already existing 

 in this locality, the following list, I think, comprises most of those which are 

 of prominent importance, namely :- — 



Bats — entirely insectivorous, and of which, I believe, we have more than 

 one species, but the individuals do not appear to be very numerous. 



Gulls and terns, or sea-swallows — visiting the fi^elds in flocks, and picking 

 up slugs, worms, and grubs. 



Larks — of which we have one species only — and a few small birds seen in 

 the bush, and in our gardens. 



We have also the Zosterops^ commonly called " blight-birds," from their 

 feeding on the American blight (Aphis lanigera), but they, though there is 

 no direct evidence of their introduction, are considered not indigenous. 



Lizards, spiders, dragon-flies, which are all entirely insectivorous. 



Beetles, of which we have numerous species of the Carahidce family, whose 

 habit is (to use the words of Dr. Carpenter) " to prowl about on the surface of 

 the ground, under stones, etc., beneath the bark of trees or moss growing upon 

 their roots, in search of their insect prey, which consists chiefly of herbivorous 

 species of their own order. Some of them nocturnal in their habits, feeding on 

 cockchafers and other species of herbivorous beetles that fly abroad during the 

 night." And two species at least of the family of the Coccinellidce, commonly 

 called "lady-birds," or "lady-cows," whose larvae feed entirely upon Aphides. 



Flies — of which we have two species most destructive to moths and flies, 

 namely, Asilus varius, and Doctria, (? species) which dart from their resting 

 place with exceeding rapidity, and seize their prey on the wing. 



