Reports and Proceedings — Geological Society of London. 235 



The curious, grotesquelj'-shapecl peaks of the Koh-i-Snltan range 

 are then briefly described, and especially that named Neza-i-Sultau 

 — a gigantic natural pillar of volcanic agglomerate many hundreds 

 of feet high. 



After thus describing the general character of the country, 

 Captain McMahon points out the very remarkable force and activity 

 with which certain natural agents are at present at work there — 

 namely, water, wind, sand, and extremes of heat and cold. 



In the second part of the paper General McMahon describes the 

 microscopical characters of the rocks, which consist of lavas, ashes, 

 pumice, igneous intrusive, and sedimentary rocks. The localities 

 in which ores of lead and copper, gypsum, sulphur, etc., occur 

 abundantly are also mentioned. 



Some andesites are described, which are especially interesting 

 from a petrological point of view. Rosenbuscii mentions that a 

 brown hornblende occurs in some rocks in which the angle of 

 extinction varies from small to nil. Some of the andesites described 

 abound in amphibole, red-brown in transmitted light, which possesses 

 the optical, properties and specific gravity of anthophyllite, and 

 which uniformly exhibits straight extinction. It is an original and 

 not a secondary mineral. 



These anthophyllite-bearing augite-andesites also contain olivine 

 — a mineral rare, but not unknown, in this class of rocks. 



2. " On the Association of Sigillaria and Glossopteris in South 

 Africa." By A. C. Seward, Esq., M.A., F.G.S., University Lecturer 

 in Botany, Cambridge. 



In this paper the author describes in detail several specimens of 

 fossil plants submitted to him by Mr. David Draper, of Johannesburg. 

 His conclusions as to the geological age of the plant-bearing beds 

 differ from those arrived at by Mr. Draper from stratigraphical 

 evidence ; the plants point to an horizon which may be referred to 

 what is now termed the Perrao-Carboniferous age. The difficulty 

 of distinguishing between various forms of Glossopteris-\e-dves is 

 discussed at some length ; and the opinion expressed that it is 

 practically impossible to separate the Indian, Australian, and African 

 forms of G. Broioniana, G. indica, and others. The chief interest 

 as regards the plants centres round the specimens of Sigillaria ; 

 these are fairly well preserved impressions, and are referred to 

 the well-known species, S. Brardi. In addition to various forms of 

 the genus Glossopteris and the specimens of Sigillaria, the following 

 plants are recorded : — Noeggerathiopsis Hislopi, Gangamopteris 

 cyclopteroides, Phyllotheca, Conites sp., Cardiocarpus sp., and 

 Splienopteris sp. 



The paper concludes with some general i-emarks on botanical 

 provinces in the Northern and Southern Hemispheres, and the 

 relation of the Glossopteris-^oxdi to the Coal-measure vegetation 

 of Europe. 



3. " Notes on the Occurrence of Sigillaria, Glossopteris, and 

 other Plant-remains in the Triassic Eocks of South Africa." By 

 David Draper, Esq., F.G.S. 



