A survey of the Phytogeography of Ihe Arctic American Archipelago 165 
over the problem of immigration. A » + > here stånds for a more or less uniform 
range over this large island, absence of records from the western coast, however, 
not being taken into consideration, as we know far too Httle about that part of the 
land to allow an inference to be drawn from this deficiency. By far the largest 
part of the Ellesmereland flora presumably has arrived from the west, and in some 
cases we even have undeniable proofs of it. Some species are found on the south 
and west coast, as well as in the far north, but not in the eomparatively well 
explored and favourable Hayes Sound region, others in the south and north alone, 
or in one of these regions. These will doubtless be found in future oii the west 
coast also, or at least they must have hved there during the warmer period. The 
letters in the column denote such different ranges within the land. All species in 
the table are found in the western islands of the Archipelago with the exception 
of the last six to which I shall return in the following. The two last columns give 
the southem hmits of the species in Greenland — as far as they have arrived 
there at all. 
I have deemed it profitable to hold apart the geographic groups of table V 
here also, and so we can see that of the 28 western species of Ellesmereland 
(groups W and W 2) five only are absent from Greenland. To them perhaps 
Agropyrum violaceum ought to be added, as its Greenland range may be without 
connection with the Ellesmereland locality, but it may as well be a northern immi- 
grant. All the others are found either in northwestern or northeastern Greenland, or in 
both those regions, and show a more or less unbroken distribution to the south, 
generally reaching farthest down on the west coast, where the way has been 
shortest. To reach the east coast, they have first had to wander north beyond the 
82". The two last species of the table most probably will find their place here 
also, when their distribution is more completely explored. For no less than 27 
species out of 62 in the ubiquituous groups U and U 2, the table shows that we 
must assume the same origin, i. e., in Greenland they are to be looked upon as 
american immigrants, and even the 35 others, more uniformly distributed over 
Greenland, almost certainly have arrived there from America, partly at least over 
Ellesmereland. I shall come back to them again in connection with other american 
elements in the Greenland flora. 
The next stage in the vanishing of the inland ice was the retreat of the 
Keewatin icesheet so far to the east as to allow plants to reach King William 
Land and Boothia Felix, hut the flora that arrived hei-e first must have come from 
the west. Låter eastern species could arrive also, but this way has not been of 
any importance for the northward immigration, only two species Atropis 
and A. Vahliana, being found here and farther north, but neither to the 
east. Both, however, are such as are very easily overlooked and ^ 
found to have a wide distribution in the southem islands. Three other plants are 
only found within the Boothia group, namely Aira ntropurptirea in North Somerset, 
Carex salina and Rubus Chamcemorus in King William Land. The two first may 
Lnnds Universitets Årsskrift. N. F. Afd. 2. Bd 9 21 
