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the rocks are gneiss, often massive. In Glen Firmilee is a series which the 
author regards as newer and Pebidian. At Farofern are quartz rocks which 
the author identifies with those beneath the limestone in Glen Laggan, near 
Loch Maree, and probably of Silurian age. At Bannavie is a granite which 
the author considers to be Pre-Cambrian. 
(2) Fort William, and Glen Nevis. — In this district chloritic schists and 
gneiss occur, which the author regards as Pebidian. 
(3) Ballachulish, Glen Coe, and Black Mount . — Chloritic schists and 
quartzites occur here, followed near Loch Leven unconformably by Silurian 
rocks. On the east of the Ardsheal peninsula, there is granite, which the 
author believes to be Pre-Cambrian. Going eastward from Ballachulish we 
have slates, probably of Silurian age. In Glencoe are granite-banded 
felsite, gneiss, breccia, resembling as a whole the rocks of the "Welsh Arvo- 
nian group. Between the Black Mount and Loch Sullich are traces of a 
great Pre-Cambrian axis, bringing up the gneissic series; this is traceable also 
towards Glen Spean and Loch Laggan to the N.E. 
(4) Tyndrum to Callander. — South and east of the former are gneisses 
and silvery mica-schists. Crystalline limestones and serpentines are associ- 
ated near Loch Tay, resembling those in the Pebidian series of North 
Wales. 
Dr. Hicks states that the Silurian (and Cambrian) rocks flank the Pre- 
Cambrian in lines from N.E. to S.W., and overlap Ben Ledi on the south 
side. Thus here, as elsewhere, subsequent denudation has removed enormous 
masses of the more recent rocks, only here and there leaving patches of these 
in folds along depressions in the old Pre-Cambrian floor. 
Fossil Glutton in Britain . — Mr. E. T. Newton has announced, in the 
Geological Magazine for April, and in a paper read before the Geological 
Society, the occurrence in the forest bed of Mundesley, Norfolk, of a portion 
of the lower jaw of a glutton ( Gulo luscus~), a carnivorous mammal now con- 
fined to high northern latitudes. The specimen shows the first true molar, 
and the hinder half of the fourth pre-molar in place, and thus furnishes all 
requisite characters for its identification. It is rather smaller than the same 
part in the recent glutton. This is the first discovery of the animal in a 
fossil state, except in caves. 
Fossil Chelonia. — Professor Seeley has announced to the Geological 
Society that after a careful examination of the specimen which Yon Meyer 
described as probably representing an Edentate mammal, allied to Glyptodon, 
under the name of Psephophorus polygonus, he found that, as surmised by 
Professor Fuchs, it was really a Chelonian allied to the Leathery Turtle 
(Sphargis). The dermal skeleton is made up of irregularly polygonal plates 
of various sizes, closely resembling those of Sphargis, except that each plate 
is almost twice as large as those of that form. The plates usually show a 
radiate ornament on the surface. On the underside of the slab are the re- 
mains of several vertebrae, apparently from the base of the neck, and these 
differ from the vertebrae of all known Chelonians in having strong transverse 
processes for the attachment of ribs. The neural arch, like the processes, 
is anchylosed to the centrum. The author considers that the dermal skeleton 
is not represented in the carapace of ordinary Chelonia, but is represented by the 
granulations on the surface of the carapace of the Trionychidae. He is hence 
