I have just been quoting you in my essay on ice carrying seeds in the southern hemisphere, but this will not do in all the cases.

I have had a week of such hard labour in getting up the relations of all the Antarctic flora from Hooker's admirable works.

Oddly enough, I have just finished in great detail, giving evidence of coolness in tropical regions during the Glacial epoch, and the consequent migration of organisms through the tropics.

There are a good many difficulties, but upon the whole it explains much.

This has been a favourite notion with me, almost since I wrote on erratic boulders of the south.