Prof. Bonney—Crystalline Schists of the Alpine Chain. 509 
I will now notice a few sections which have been repeatedly 
quoted as proving the later Paleeozoic or earlier Mesozoic age of true 
crystalline schists.’ 
1. In 1881 I was informed by a Swiss Professor of Geology that 
the well-known conglomerate of Carboniferous age in the Waloraite 
near Vernayaz exhibited partial metamorphism, “mica scales, large 
enough to be seen with the unaided eye, having been developed in 
situ. After visiting the sections and examining the rocks under the 
microscope I had no doubt that the mica was derivative, like the 
. fragments of gneiss, etc.” 
2. Some foreign geologists have claimed the crystalline schists on 
the mountains near Zermatt, on either side of that branch of the 
Vispthal, with their prolongation eastward to the neighbourhood of 
Saas, as metamorphosed rocks of early Mesozoic age. The only 
evidence that I have been able to find for this identification is that 
here and there a little strip of ordinary rauchwacké (Trias) is nipped 
in among normal crystalline schists, which seems to me, as will be . 
more fully shown in the next instance, strongly adverse to that 
conclusion. 
8. The Val Canaria and Val Piora sections.—Here we find a group 
of mica-schists, often calcareous and sometimes passing into marbles, 
apparently infolded in rauchwacké, the most impressive section 
occurring in a ravine on the right bank of the Val Canaria. But I 
have shown this to be an impossible interpretation, if only from the 
fact that the rauchwacké contains abundantly fragments of the 
schists which are supposed to overlie it. We obtain similar evidence 
on the upper part of the Lukmanier Pass some seven miles to the 
E.N.E., as well as at a rather greater distance to the W.S.W. 
between the Nufenen Stock and the Gries Pass.‘ 
4. Another group of sections has been supposed to prove that 
certain staurolite and black-garnet schists (well developed near the 
Lago di Ritom) pass into schists in which these minerals (authigenous) 
occur with fairly well preserved belemnites and ossicles of crinoids. 
This assertion can be tested in sections on Scopi to the east of the 
Lukmanier Pass, between All’Acqua and the Nufenen Pass, and on 
the northern ascent to the Gries Pass.> In some cases the garnet- 
bearing mica-schist is parted by a little rauchwacké, from the fossili- 
ferous schist (supposed), but in others the two are in sequence. The 
occurrence of fossils in the latter is indubitable, but the minerals 
claimed as garnets and staurolites are only secondary hydrous 
minerals, too impure for precise identification, and their matrix is 
not a true schist. In fact, these sections prove nothing more than 
1 The stock instance of gneisses and Jurassic limestones on the northern 
crags of the Jungfrau is now abandoned, so it needs no discussion. 
2 GEOL. MaG., 1883, p. 507. 
3 See Q.J.G. S. 4 1890, pp. 199-211; 1894, pp. 297-300. There are four 
marked varieties of these schists, three of which I have found in the rauchwacké 
and the fourth at the base of the Lias near the Lukmanier Pass, where this 
rock rests directly on that particular schist. 
+) Q@:J.G.8., 1893, pp. 90-1. 
> Q.J.G.S., 1890, pp. 213-21; 1893, pp. 90-1. 
