290 Transactions. — Zoology. 



few years inclosiires and cultivation have been rapidly extending around 

 Christcliurch, and forming a nursery for the preservation and increase of the 

 insect race. A luxuriant and abundant vegetation has sprung up for its food 

 and shelter, and it is comparatively freed from the ravages of fire and the 

 attack of its feathered foes. WLat can we expect under such circumstances 

 but to be visited with an insect pest % Unless some remedy were applied, 

 or some special intervention of Providence occurred, the evil would inevitably 

 increase with each succeeding year, and the farmer would ultimately find 

 that his money and labour were providing but a harvest for the caterpillar 

 and grub. 



Some idea may be formed of the enormous increase of herbivorous insects 

 if we take, for example, Plusia gamma, one of the moths of the Noctuce family 

 (a family extensively represented in this neighbourhood) and the common 

 Aphis or plant louse. H^aumer has proved that from a single pair of Plusia 

 ga^nma moths, 80,000 might be produced in one season, and the rapidity of 

 production of the Aphidoi is so enormous, that nine generations have been 

 produced in three months ; and, each generation averaging 100 individuals, 

 it has been calculated that 10,000 million millions may be generated in that 

 period from a single Aphis. 



So far as I have been able to ascertain, from inquiry and from my own 

 personal observations, the insects which appear to have been the most injurious 

 to the farmers of this neighbourhood are of the following kinds, namely :— 



Of moths five species, namely — Pielus umbraGulatus, Gu., Pielus vario- 

 laris, Gu., and Cloantha cptnposita, Gu., (all named and described by 

 M. Guen^e as " new species " from specimens taken by me in this 

 province), and Heliothis armigera and Sesia tipuliformis (a species 

 found also in England). 

 Of Beetles two species, namely — Odontria striata and Odontria (n.s. 



und escribed). 

 Of Aphides, several species. 

 Several specimens of the perfect insect of each of the above species of 

 moths and beetles I now place before you for inspection, and in order that 

 you may identify the species to which I allude. 



Pielus umbraculatus and P. variola^'is make their appearance on the wing, 

 in great numbers, in the evening twilight, and in the daytime are found at 

 rest on posts and rails and palings and such like places, and numbers may be 

 seen entangled or wound up in the webs of spiders. These moths are very 

 abundant in the months of October and November. The family to which 

 they belong has received the common name of " swifts " from the rapidity of 

 their flight. The larvse of these species are short fleshy grubs, having six 

 pectoral, eight ventral, and two anal feet; they are subterranean, and feed 



