3028 Reports and Proceedings— 
The minerals noticed in this paper occur in a bed of grey limestone 
in the Carboniferous Limestone at Lilleshall. They occur in vertical 
joints in the upper subdivisions of the bed. The following list gives 
them arranged in order of frequency, the least common being placed 
first: —quartz, bornite, towanite, iron-pyrites, hematite, barytes, 
calcite, dolomite (ankerite?). Of the first, the author has only met 
with a single minute crystal. Iron-pyrites is by no means common ; 
hematite is more abundant. Of analyses of two specimens of the 
“dolomite,” one agrees very nearly with ankerite, while another, 
identical in aspect, exhibits considerable differences, being only a ferri- 
ferous dolomite. The author suggests that it is doubtful whether 
ankerite should be retained as a mineral species. 
3. ‘Fossil Chilostomatous Bryozoa from Muddy Creek, Victoria.”’ 
By A. W. Waters, Esq., F.G.S. 
In this paper the author described a collection of fossil Bryozoa, 
collected and sent over by Mr. J. Bracebridge Wilson, of Geelong. 
The collection is from Muddy Creek, Bird Rock, and Wauru Ponds, 
Victoria, and is of the so-called ‘‘ Miocene’”’ age. There are 64 species, 
of which 28 are known living, and 18 of these are now found fossil for 
the first time; but of the rest a large number have previously been 
found and described from Curdies Creek, Mount Gambier, and Bairns- 
dale. The author considered that 28 out of this number being known 
living is a large proportion, seeing that although our knowledge of the 
Australian recent fauna has been much increased during the last few 
years, it yet is very imperfect. 
The collection furnished 13 species of Catenicella, of which 5 at 
least are known living; and the author indicated the great importance 
of a thorough study of the living species of that genus. A notch in 
the aperture simulating a sinus seems sometimes to be replaced by a 
suboral pore, and a plate on the front of the cell requires further 
investigation. 
Three species are believed to be identical with fossils from the 
European chalk. 
IJ. — May 23, 1883.—J. W. Hulke, Esq., F.R.S., President, in 
the Chair.—The following communications were read.:— 
1. ‘‘On the Basalt-glass (Tachylyte) of the Western Isles of Scot- 
land.’”? By Prof. J. W. Judd, F.R.S., Sec. G.S., and G. A. J. Cole, 
Esq., F.G.S. 
Basalt-glass or tachylyte is a rare rock, although very widely dis- 
tributed. 
In the Western Isles of Scotland it has, by the authors of the paper, 
been detected in five localities only, namely, Lamlash (Holy Isle) near 
Arran, the Beal near Portree in Skye, Gribun and Sorne in Mull, and 
Screpidale in Raasay. 
Basalt-glass is always found in the Hebrides as a selvage to dykes, 
though elsewhere it has been described as occurring under other 
conditions where rapid cooling of basaltic lava has taken place. Some 
of the varieties of basalt-glass in the Hebrides differ from any hitherto 
described by their high specific gravity (2°8 to 2°9) and by their low 
percentage of silica (46 to 50). 
