Bd. III: 7) 
ADDENDUM. 
43 
and, as this dyke traverses the beds surrounding the glauconitic bank, it follows, as 
a most important consequence of Mr. Buckman’s determination of the age of this 
bank, that the period of the basalt-eruptions is of no earlier date than Oligocene- 
Miocene times. Because of the striking parallelism in geological features of Graham 
Land and S. America where Tertiary beds (Oligocene-Miocene according to Wilckens) 
are traversed by numerous basalt-dykes and underlie a coarse ba,salt-tuff, I put 
forward the supposition that the basalt-eruption of Graham Land was also post- 
Oligocene-Miocene ( 1 . c. p. 6i). This presumption has now gained unexpected 
and most valuable support from Mr. Buckman’s determination of the age of the 
glauconitic bank. 
As mentioned above and more fully described in my paper of 1906, at loc. 12 
there rests on the basalt-tuff formation a small patch of a conglomerate containing 
a big Pecten and several other fossils. In the above-cited paper I have compared 
this conglomerate with the Parana formation and the Cape Fairweather beds of S. 
America and supposed it to be very young Tertiary or very old Quaternary, most 
probably Pliocene. Now Mr. Buckman has come to the conclusion, after his examin- 
ation of the Brachiopoda contained in the conglomerate, that its age is probably 
Pleistocene. 
Judging from the purely littoral character of the deposit, combined with the 
composition of its fauna, it seems evident that the conglomerate was not formed during 
glacial conditions: such an abundance of littoral shells being absolutely impossible on 
a coast heavily attacked by pack-ice and icebergs. Thus the A^’r^tv^-conglomerate 
must have been deposited before the beginning of the glaciation of the Antarctic 
region. Since, however, Mr. Buckman has suggested that the conglomerate is most 
probably Quaternary, we must suppose that even the beginning of the glaciation of 
these tracts falls into the Quaternary period. 
The age of the A^’r/é’/z-conglomerate is interesting also from another point of 
view. It seems highly probable that Cockburn Island, at the time when this conglo- 
merate was being formed, did not exist as an isolated tract, but that its level area, 
upon which the conglomerate rests, then extended much farther, and was probably 
connected with the neighbouring plateau-areas. If this supposition is correct, the 
denudation which formed Admiralty Sound and isolated Cockburn Island, must have 
taken place in Quaternary time. 
In my paper of 1906 I compared the Pecten-conglomerate with the Paranä-Cape 
Fairweather beds of South America, considering them to be of the same age. The 
South American strata are regarded as Pliocene; but if the A^’c/'iS’/z-conglomerate 
proves to be Quaternary, the question of the age of the said S. American deposits 
may need revision. 
