The President said it was impossible with him to overcome the geological difficulty in the way of a supposed former land-connection; for though he could readily believe in great elevation or depression, either continuous or alternate, yet it was a generally received opinion that the great depths between these islands and the continent of Europe had existed since the secondary period. The example of Keeling Island, as noticed by Mr. Murray, was of little importance, because, being a coral island, it was of very recent date, and, as there was little variety of vegetation, it was impossible for the insects to show great increase; but, let the island become more elevated, and its flora more varied, then its few involuntary insect immigrants would each become the nucleus of a group of generic forms. Mr. Murray had not explained the greatest objection to Mr. Wollaston's theory, the wonderful absence in the Atlantic Islands of indigenous mammals and reptiles, which, if the islands be the remnants of a once-existing continent, ought certainly to be represented; neither did he account for the absence of the apterous groups of bulky European heteromerous beetles, such as Pimelia, &c., an absence the more remarkable in the face of the fact that genera, and even species, of other families, become apterous in the islands, though they are winged in Europe.