162 Rhodora [JULY 
in which they delight, these plants would have found the long belt 
of pine barren region of the bridge as forbidding to them then as are 
such habitats today. Similarly, though the caribou, Arctic hare, 
ptarmigan and other boreal animals of Newfoundland, would find 
the bridge congenial territory, the moose, porcupine, and other 
mammals of the Canadian forest would find little inducement to leave 
the denser woods to wander far upon the sand-bridge, and for this 
reason apparently they failed to accompany the vole and the muskrat 
(as well as the caribou, etc.) to Newfoundland. 
To summarize briefly, the indigenous flora of Newfoundland consists 
primarily of plants which occur .to the north, in Labrador, or to the 
southwest, chiefly along the Atlantic seaboard or the Coastal Plain; the 
typical Canadian plants, unless their northeastern range extends to the 
north side of the Straits of Belle Isle, being essentially absent from the 
island. The distance between Newfoundland and Labrador is not 
sufficiently great to prevent ready interchange of species across the 
Straits of Belle Isle, but the distance between Newfoundland and 
Cape Breton is so great that the plants of the latter region rarely if 
ever span it. Birds, ocean-currents, drifting logs and ice, and winds 
prove to be ineffective in carrying to Newfoundland the plants from 
the southwest, so that an ancient land-bridge is suggested. This 
is the more demanded from the presence in Newfoundland of a vole 
and a muskrat, mammals closely related to species of our coastal 
region. The amount of water withdrawn from the ocean to form the 
Pleistocene glaciers was apparently sufficient to leave exposed nearly 
if not all the old coastal plain which now forms the submerged bench 
off our coast, and in addition there is unquestioned evidence that 
since the Glacial Period this coastal bench has been much higher than 
it is now; so that upon this now submerged plain, as the ice-front 
receded northward, the southwestern plants, most of which still occur 
on Cape Cod, Long Island or in the Pine Barrens of New Jersey, 
must have spread to Newfoundland, where now they form an isolated 
flora. 
