494 eeder =Suawas 
A. On the Geological Relations and Mode of Preservation of Bozoon cana- 
dense. By Principal J. W. Dawson, C.M.G., F.R.S. 
The oldest known formation in Canada is the Ottawa gneiss, or funda- 
mental gneiss, a mass of great but unknown thickness, and of vast area, consistin 
entirely of orthoclase gneiss, imperfectly bedded and destitute of Ae aang 
quartzite, or other rocks which might be supposed to indicate the presence of land- 
surfaces and ordinary aqueous deposition. It constitutes the lower part of the Lower 
Laurentian of Logan, and may be regarded either as a portion of the earth’s 
original crust, or as a deposit thereon by aqueo-igneous agency and without an 
evidence of derivative deposits. y 
Succeeding this is a formation of very different character, though still belonging 
to the Lower Laurentian of Logan. It may be named the Grenville series oan 
includes beds of limestone, quartzite, iron ore, and graphitic and hornblendic schists 
with evidence locally of pebble-beds. It is in this, and especially in one of its me: 
limestones, the Grenville limestone, that Kozoon canadense occurs. It Sihini Sacer 
that these limestones are regularly bedded and of great horizontal extent. The 
Grenville formation presents lithological evidence of ordinary atmospheric panied 
of the older rocks and of ordinary aqueous as well as organic deposition 
Above this is the Norian series, or Upper Laurentian of Logan, in whisk ies 
felspars become dominant, and show that the calcareous rocks accumulated in the 
preceding period were already contributing to the material of new deposits. No 
evidence of Eozoon has been found in this formation, which is thus far exitirel 
unfossiliferous. y 
The Huronian and other series, also eozoic or pre-Cambrian rocks, overlie the 
Norian, and in one of these, the Hastings group, belonging probably to the Taconian 
of Hunt, specimens of Eozoon and indications of worm-burrows and other obscure 
fossils have been found. 
With reference to the mode of preservation of Eozoon, it was stated that in its 
ordinary condition, as mineralised by Serpentine, it presents the simplest kind of 
mineralisation of a calcareous fossil, that im which the original calcite walls still 
exist, with no change except a crystallisation of the calcite common in the fossils of 
newer formations, and with the cavities filled with a hydrous silicate which was 
evidently in process of deposition on the sea-bottom on which Eozoon is supposed to 
have lived. Commencing with this fact, the author proceeded to show that the 
various imperfections and accidents of preservation observed in Kozoon are precisel 
parallel to those observed in paleeozoic and mesozoic fossils. y 
Tn conclusion it was stated that many new observations had been made by Dr 
Carpenter and the author, and would appear in a memoir now in ofhting of 
preparation by the former ; and that the author hoped, on occasion of the visit of 
the British Association to Canada next year, to exhibit to those interested in the 
subject the large series of specimens now in the museum of McGill University. 
5. On. the Geological Age of the North Atlantic Ocean. By P. x 
Epwarp Hutt, LL.D., F.RS. Y Eapeeaaon 
In this paper the author made use of three leading formations, as f: in hi 
inquiry, viz., the Aychzean (or Laurentian), the Silurian (chiefly ii Bade ps hay 
and the See beets ws? 
‘1) Dealing with the Archzean, he traced its range both throug cr 
(eee, continent, and that of Europe and the British Isles, tien: 8 aaacmie 
is every reason for concluding that the strata of this age underlie all the more 
recent formations of these tracts, and assuming that the metamorphic beds (con- 
sisting of granite or gneiss, hornblendic and other schists, quartzites, &c., of pre- 
cambrian age), were originally oceanic sediments, he drew the inference that the 
originating lands of these sediments were situated in the region intermediate 
between North America and Europe, in other words, in the Central and North 
Atlantic region, probably including Greenland. 
