230 THE JOURNAL OF GHOLOGY. 
greater part of the Archean area was never covered by Palzozoic 
rocks is inconclusive, since it is stated that the pre-Palzeozoic topogra- 
phy of the area covered by Paleozoic rocks is the same as that not so 
covered. 
Adams* gives a preliminary description of Sheet 118 of the Canadian 
Survey, an area of about 3500 square miles, situated north of Lake 
Ontario, in the counties of Victoria, Peterborough and Hastings. The 
whole area is occupied by the rocks of the Laurentian system, with 
the exception of the southeast corner, which is underlain in part by 
the Hastings series. In the surrounding eastern portions there is an 
abundance of crystalline limestone, and the rocks have all the character- 
istics of the Grenville series of Sir William Logan. In the north- 
western part of the area the country is apparently occupied by gneiss 
alone. The relations of the Grenville series to the gneiss free from 
limestone has not yet been definitely determined, although the lime- 
stone and the associated gneiss seem in certain cases to partially enclose 
areas which contain no limestone. ‘Throughout the area occupied by 
the Laurentian rocks, the dip, are uniformly at an easterly direction, 
usually at moderate angles. Only at one or two points have westerly 
dips been observed, and these are quite local. ‘The relations of the 
Hastings series to the Laurentian is also as yet uncertain. One of the 
most marked characteristics of this district is the great development of 
pyroxenic and hornblendic rocks, among which many are, without 
doubt, of eruptive origin. Also there are several large intrusive 
masses. of granite, and a very extensive mass of nepheline syenite. 
Otherwise the Hastings and Grenville series are not very unlike 
petrographically. 
In the area south of Sheet 118, in Dalton and the western part of 
Digby townships, is found reddish orthoclase gneiss, with dark, mica- 
ceous and hornblendic bands, which is cut in a complicated way by 
coarse-grained granite. In the eastern part of Digby township and in 
Lutterworth and Galway townships are found crystalline limestones, 
and the peculiar rusty weathering gneisses always associated with them. 
In the limestone districts various metalliferous ores are found. 
‘Preliminary Report on the Geology of a Portion of Central Ontario situated 
in the Counties of Victoria, Peterborough and Hastings, together with the results of 
an Examination of Certain Ore Deposits Occurring in that Region, by F. D. ADAms. 
Geol. Sur. of Can., Ann. Rep., Part I., Vol. VI., pp. 15, 1894. 
