Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/665

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pany with Prof. Hind, in the winter of 1868, at which time the mining on the lodes referred to in the map before the Society was at a standstill, the lodes having been lost by reason of a fault. He thought it was very satisfactory to find that the theoretical position which Prof. Hind, from his explorations, assigned to the lodes had been completely verified. Mr. Robinson also stated that gold is being mined in the synclinals by sinking shafts and driving cross cuts.

Mr. Hind remarked that all the Lower Silurian in Nova Scotia was auriferous, and that the gold was derived from the underlying Laurentian rocks. He stated that Sir W. E. Logan had indicated an auriferous zone in the Laurentian of Canada. Gold was finely distributed in the slates of Nova Scotia, as in Victoria, in the neighbourhood of lodes, according to Mr. R. Brough Smyth.

May 11, 1870.

Sir William Bagge, Bart., M.P., of Stradsett Hall, Market Downham, Norfolk ; Colonel James Leslie Tait, of Montgomery, Alabama, U.S., and Dr. C. C. Caruana, of the Malta University, were elected Fellows of the Society.

The following communications were read : —

1. Notes on some specimens of Lower Silurian Trilobites. By E. Billings, Esq., E.G.S., Palaeontologist of the Geological Survey of Canada.

(Plates XXXI. and XXXII.)

1. Asaph us platycephalus, with some of the legs preserved. This specimen was collected in the Trenton Limestone, at the city of Ottawa, about ten years ago. "When discovered it was lying flat upon a thin slab of limestone, and well preserved, with the exception of the eyes, which seem to have been forced inwards by pressure from above. It was also divided into two pieces by a fissure which extended diagonally across, from the first segment of the thorax on the left side to the fifth segment on the right.

It remained in the Museum for several years without attracting particular attention, until one day, observing that the part in front of the fissure was somewhat loosely attached, I removed it, and was surprised at finding, on the underside, not only the hypostoma in place, but also what appeared to be some of the legs of the animal. As the part behind the fissure was more firmly attached to the stone, I had it cut across just behind the eighth segment by the lapidary of the Survey. The remainder of the thorax was then easily split off. The pygidium came off with difficulty and in two pieces. All the pieces were then fastened together ; and we thus obtained two specimens, one of which shows the underside of the Trilobite, and the other its impression on the stone.

On the underside (Pl. XXXI. fig. 1) a broad shallow groove extends