The following communication is introductory to a few remarks on the Nova Scotian and Canadian Insects which I have received through the kindness of J.M. Jones, Esq., W. Saunders, Esq., and Prof. Croft.

The study of the geographical distribution of Insects has become more interesting by the differnece of opinion as to the origin and diffusion of species. The insects of seperate arctic regions have a great muttual resemblance, and the difference between them increases in the successive concentric circles from the above regions towards the equator.