Geological Society of London. 45 
the Buffalo ; isolated pinnacles of it occur at the spot where the few 
survivors of the fight crossed that river. A range of mountains, 
witb mural escarpments, remnants of an ancient plateau, rising to a 
height of some 2000 feet above another plateau which is 5000 to 
6000 feet above the sea, extends for about 500 miles from the north 
of Natal to near Cradock in the Cape Colony; they are sandstone 
horizontally stratified, capped by trap. Some other geological 
features are described. The Transvaal consists of undulating hills 
of soft limestone, a sandstone range, and a country rich in metals— 
iron-ore, cobalt, nickel, copper, and gold occur, as well as plumbago. 
II.—December 8, 1879.—-Henry Clifton Sorby, Esq., F.R.S., Pre- 
sident, in the Chair.—The following communications were read :— 
1. “The Gneissic and Granitoid Rocks of Anglesey and the 
Malvern Hills.” By C. Callaway, M.A., D.Sc., F.G.S.; with an 
Appendix on the Microscopic Structure of some of the Rocks, by 
Prof. T. G. Bonney, M.A., F.R.S., Sec.G.S. 
The author described the results of his investigations into the 
stratigraphy and petrology of the above districts, which have led 
him to the following conclusions: — 1. The granitoid (Dimetian) 
rocks of Anglesey pass down into an anticlinal of dark gneiss (above) 
and grey gneiss (below). 2. Associated with the granitoid series are 
bands of felsite, hilleflintas, and felspathic breccias. 38. The suc- 
cession of gneissic and granitoid rocks in Anglesey resembles so 
closely the metamorphic series of Malvern as to justify the correla- 
tion of the two groups. 4. The Pre-Cambrian rocks of Anglesey 
and the Malverns, from the highest known member down to the 
base of the gneiss, may be thus classified :—A. Pebidian (to be de- 
scribed hereafter); B. Malvernian; (a) Dimetian, with associated 
quartz-felsites and hialleflintas (Arvonian) passing down into (b) 
Lewisian. 
2. “ Petrological Notes on the Neighbourhood of Loch Maree.” 
By Prof. T. G. Bonney, M.A., F.R.S., Sec: ~ 5. 
The author had visited the upper end of Loch Maree and its 
vicinity with a view of seeing whether microscopic examination 
threw any light on the vexed questions as to the age of the newer 
gneiss, etc. He described the microscopic structure of a typical 
series of the Hebridean gneiss, and gave reasons for considering the 
mass of rock on the right bank of Glen Laggan to be not an intru- 
sive “syenite,” as has usually been supposed, but a mass of the 
Hebridean gneiss faulted against the newer series. The microscopic 
structure of the Torridon Sandstones was described ; it proves that, 
as previously asserted, they are made up of the débris of the Hebri- 
dean series; from this also probably came the materials of the 
quartzites. By examination of specimens, collected both in Glen 
Laggan and at other points along the northern escarpment of the 
newer series, the author showed that its rocks have been rightly 
called metamorphic; and then, by comparison of these with speci- 
mens collected in Glen Docherty, he concluded that the latter 
belonged to the newer series, and that no part of the Hebridean 
