ON LIFE-ZONES IN THE BRITISH CARBONLFEROUS ROCKS. 317 
Mr. Tait, collector of the Geological Survey of Scotland, has been 
examining the Millstone grit succession east of Lancaster this summer, 
and Mr. Watson, of Owens College, has been working in the upper part of 
the Valley of the Nidd. It has not been possible to examine their collec- 
tions in time for this report. 
The Secretary was fortunate enough to secure a fine collection of 
plants obtained in an abortive attempt to find coal at Thirshfield, near 
Grassington, in the Valley of the Wharf. The exact place of the sinking 
is lat. 54° 3’, long. 2° 2’, and the shales are stated to be those which 
occur below a bed of Millstone grit. 
Mr. Kidston has kindly examined the specimens for him, and the 
following list is the result :— 
Sphenopteris elegans Bet. Sphenophyllum tenerrimun Ett. sp. 
Calymmatotheca Stangeri Stur. Lepidodendron sp. 
Rhodia Moravica Ett. sp. Lepidostrobus sp. 
Sphenopteris sp. Small Lycopodiaceous bract. 
Calamites Ostraviensis Stuy. Rihabdocarpus? sp. 
Calamites sp. 
Mr. Kidston states, with regard to the horizon: ‘I have not the 
slightest doubt that the bed these specimens come from is on the horizon 
of the Upper Limestone group of the Carboniferous Limestone series of 
Scotland.’ At any rate we know that the Lower Limestone group of 
Scotland has a fauna which indicates the Upper Dibunophyllum zone, 
Composition and Origin of the Crystalline Rocks of Anglesey.—Second 
Report of the Committee, consisting of Mr. A. HARKER (Chairman), 
Mr. E. GREENLY (Secretary), Mr. J. Lomas, Dr. C. A. Mat.ey, 
and Professor K. J. P. ORTON. 
APPENDIX.— Methods of Rock Analysis. By JOHN OWEN HuGHES. + page 323 
As stated in the Interim Report for last year, the problem first selected 
for a work has been that of the origin of the hornfels and other meta- 
morphic rocks of the heart of the island. These rocks have been variously 
described as ‘halleflinta,’ pelite, and altered felsite. As their field- 
relation and microscopic characters will probably be discussed before long 
in another place, and as the analytical work is still incomplete, sufficient 
only will be said here to give an idea of the present nature of the rocks 
and the objects of the analysis. The numbers attached are those of the 
slides in the Secretary’s cabinet, and the localities are referred to sheets 
of the Six-inch Ordnance maps. 
The analyses given have been drawn up by Mr. John Owen 
Hughes, B.Sc., giving full details concerning the work, nearly all of which 
has been executed by himself. Unless otherwise stated the analysis is by 
Mr. Hughes. 
No. 2154, 100a, 4004. These are all from the typical hornfels, and 
selected as varieties of it. They are fine-grained, dull, greenish rocks, 
with sometimes a slight schistosity, and are composed of quartz, with 
chlorite, fine mica, some iron ore, and accessory minerals, They do not 
differ much in microscopic structure. 
No. 1004 contains dark spots, which are aggregates of chlorite full of 
inclusions of iron-ores and other minerals. 
