A survey of the Phytogeography of the Arctic American Archipelago 27 
are always in an arctic land far inferior to those of the inner land — provided 
that it is not entirely glaciated. 
Even a passing glance at some geological map of the Arctic Archipelago, for 
instance that of De Rance (Aret. Geol.) or one of thein which accoinpany the 
Reports of Low and Bernier, will immediately show, that the islands are built up 
of rocks of the most different description. From the Archaean upwards almost 
every system is represented. If we begin from the east, we shall lind Archaean 
rocks everywhere along the western side of Baffin Bay up to Hayes Sound in 
EUesmereland. Also the southern shore of Baffin Land as well as most parts of 
Melville and Boothia Peninsulas and the North Soinerset and Prince of Wales 
Island shores along Peel Sound are constituted of rocks belonging to the same system. 
Cambrian and Sihirian deposits are found in the interiör of southern Baffin 
Land and probably continue northwards, as the whole north western part of that 
large island consists of the same material. On the other side of Lancaster Sound 
they appear again in the southwestern and middle portions of N. Devon as well 
as nearly all over Cornwallis Island. In the middle southern district we find them 
again on the east side of N. Somerset and the western of Prince of Wales Island, 
as well as all over King William Land and parts of the Boothian coasts. Accor- 
ding to the three geological maps mentioned above also nearly the whole of Victoria 
Land and the southern part of Banks Land should consist of Silurian rock, but 
I have not been able to find ont any definite statements about those regions on 
which the indications in the map could be based. De Hänce, indeed, refers to 
Haugthon'8 Geol. Acc. in M'Clintock's Narrative as his source, but Hadgthon 
expressly states, that his paper is based principally on the collection of M'Clintock, 
and he has not a singie note about the western islands. He does, notwithstanding, 
draw them as Silurian, and the same designation is accepted in the låter maps. 
Therefore the question must arise, have M'Clure or Coli.inson ascertained these 
regions to be Silurian, or have they l)rought home Silurian fossils frotn there? 
Now as far as I have been able to make out neither M'Clure's nor Collin80n'8 
expeditions have determined the geological age of the rocks in those parts, even if 
they speak of limestone, and M 'Millan in Bernier's Report, although he marks 
the southwestern region as Silurian has no indication about any fossils found there. 
I am very inclined to think that the limestone of Victoria and Banks Lands may 
be younger than the Silurian system. I have entered so far upon this question, 
because it is of a certain botanical interest. When I was working in EUesmereland 
the great difference between the vegetation of the Silurian limestone ground and 
rocks of other kinds could not escape my observation, and I have referred to it 
both in my Flora Ellesm. and in Sti-ay Contrib. During the perusal of the many 
