Page:Polar Exploration - Bruce - 1911.djvu/97

Rh either by sea or ice, than there is in Arctic Regions, where on most shores enormous quantities of driftwood are stranded year after year, so much so that some places have the appearance of timber yards.

The absence of land birds, with the solitary exception of the Sheath-bill (Chionis), is against the transit of seeds, though some petrels, the Dominican Black Back Gull, the skuas, and the shags may occasionally carry seeds to these lands.

As far as the geographical distribution of plants is concerned, Skottsberg and Rudmose Brown consider the parallel of 60° S. forms a more or less natural limit. (Note how difficult it is to give a hard and fast limit for the boundary of the Antarctic Regions: the astronomer takes the Antarctic Circle, the botanist the 60th parallel of south latitude, and the oceanographer the limits of floating ice.) "The flora of the Antarctic regions," says Dr. Rudmose Brown, "as thus defined, contains only two phanerogams, namely, Aira antarctica (Hook. Des.) and Colobanthus crassifolius (Hook, f. var. brevifolius, Eng.). The former of these has long been known from Antarctic Regions, having been collected by Eights about 1820 at the South Shetlands, and it also occurs on Danco Land, but its discovery along with Colobanthus crassifolius, by Dr. Turquet, of