234 Reports and Proceedinffs. 



form. In the Menevian beds, wliich were deposited in a deep sea, the shells are 

 small. Mr. Hicks thought, therefore, that we must admit these changes to be due to 

 changes in the conditions of existence. The Lingidce had been declared to be allied 

 to the Annelids ; the Trilobites were also allied to the Annelids, and these three are 

 the earliest known forms of life. It would be well worth while to follow the inquiry 

 how far they were related. 



Prof. Ramsay was delighted to hear the opinion expressed by Mr. Davidson, that 

 the distinction of species was merely an abstract idea. He had always considered 

 that the apparent distinction of species was due to the absence of the connecting 

 links. He was thankful to Mr. Davidson for stating that in different geological 

 formations thei'e were forms which had received distinct specific names, but which he 

 could not distinguish otherwise than by their derivation. Mr. Hicks had spoken of 

 the three forms of organisms which occur deep down in the Cambrian, and founded 

 an argument upon their rarity. But Prof. Ramsay had long maintained the hetero- 

 dox opinion that the Lower Cambrian was a freshwater formation, in which marine 

 deposits are here and there intercalated. He looked forward to the future discovery 

 of marine Lower Cambrian beds with a much richer fauna, and considered that it was 

 only from accidental circumstances that the fauna of the Lower Cambrian is so poor. 



Mr. Etheridge also called attention to the poverty of the Lower Cambrian fauna in 

 Great Britain. 



Mr. Boyd Dawkins remarked that the most lowly organized forms seemed to be the 

 most persistent. 



3. "Note on the Occurrence of Sapphires and Eubies in situ with 

 Corundum, at the Culsagee Corundum Mines, Macon Co., North 

 Carolina." By Col. C. W. Jenks. Communicated by David Forbes, 

 Esq., F.E.S., F.G.S. 



The mine described in this paper is in a bill situated about nine 

 miles east of Franklin, the chief town of Macon County, rising 

 about 400 feet above the valley. The hill is a boss of serpentine 

 protruded through the surrounding granite. The corundum occurs 

 in five nearly parallel veins, cropping out for about a mile along the 

 steep side of the hill in a direction N.E. and S.W. The veins all 

 dip to the S.E. about 45°. They are thin at the surface, but widen 

 out as they descend, the thickness of the vein in the deepest working 

 (75 feet) being about 10 feet. They consist of a mass of chlorite, 

 Jefferisite, and corundum, the latter forming from one-third to one- 

 half of the mass, and occurring in crystals imbedded in the other 

 minerals. The author gives a list of several minerals which also 

 occur in the veins, including two new silicates, which Professor 

 Genth has called Kerrite and Maconite. Analyses of some of these 

 minerals and of the serpentine rock are appended to the paper. 

 Some of the crystals of corundum weigh as much as 300 pounds. 

 The corundum is crushed and used for grinding and polishing stones, 

 glass, and metal ; about 200 tons have been extracted from the mine. 

 The colour of the crystals is very variable, and some of them show 

 different colours in different parts. Many rubies and sapphires have 

 been already procured and cut for setting. 



Discussion. — Mr. WaringtonW. Smyth considered the communication made by 

 Col. Jenks as a very important and interesting one. He referred to the nature of 

 these gems, and expressed a hope that Col. Jenks's further operations might result in 

 the discovery of large and fine crystals. 



Mr. D. Forbes remarked that much credit was due to Col. Jenks for having fol- 

 lowed up the fragmentary evidence which he originally obtained with such good 

 results. The origin of these gems had long been a disputed point ; all those hitherto 

 obtained have been found in a waterworn state in the beds of streams. Col. Jenks 

 had discovered the actual home of the so-called Oriental ruby and sapphire. 



