Geological Society of London. 513 



and also some implements formed from pebbles. The organic re- 

 mains found in the first fissure belong to fourteen mammals at least, 

 besides a bird and a fish. The mammalia are — Man, Lepus timidus, 

 Gulo liiscus, Hyceiia spelcea, Ursus, sp., Canis lupus, Canis vulpes, 

 Cam's lag opus, Elephas primigenius, Equus cab alius, Rhinoceros 

 ticlwrJiinus, Bos urus, Cervus megaceros, Gervus tarandus, Ovis, sp., 

 Arvicola, sp. 



4. " Notes on Haytor Iron Mine." By Clement Le Neve Foster, 

 Esq., B.A., D.Sc, F.G.S. 



The Haytor mine is situated on the eastern borders of Dartmoor, 

 about three-quarters of a mile from the pile of granite rocks from 

 which its name is derived. 



The iron-ore occurs in the form of magnetite interstratified with 

 altered shales and sandstones of Carboniferous age, which strike about 

 E. 25° S., and dip northwards at an angle of about 30°. 



Near the iron-ore the rock becomes highly charged with horn- 

 blende, and is sometimes apparently entirely made up of actinolite. 

 Garnets occur in great abundance. 



The following section is shown in the adit level, viz. : — 



Carboniferous rock. 



Iron-ore with, partings of rock 10 ft. 



Carboniferous about 6 ft. 



Iron-ore with partings of rock 14 ft. 



Carboniferous about 3 ft. 



Granite-vein 8 in. 



Iron-ore 6 ft. 



A fourth bed, about 3 ft. thick, is seen cropping out about 300 yards 

 N.E. from the others. 



The granite-vein is intruded, not interbeclded. The outcrop of 

 these beds of magnetite may be traced eastwards for a distance of 

 about three-quarters of a mile. The author considers the iron- ore 

 to be simply an altered stratified deposit, and not an igneous trap. 



5. " On the Formation of the Polar Ice-cap." By J. J. Murphy, 

 Esq., F.G.S. 



The present paper is intended by the author to supplement a 

 previous one, read before the Society in 1869 (Q. J. G. S. vol. xxv. 

 p. 350), in which he gave reasons for differing from Mr. Croll in 

 thinking that the glacial climate was one of intense cold, and held, 

 on the contrary, that it was one of snowy winters and cold summers, 

 with a small range of temperature. 



Mr. Campbell, in a paper read before the Society in 1874, gave 

 the following as the southernmost limits of the Polar ice-cap, viz. : — 

 In Eastern Europe lat. 56° N. ; in Germany 55° ; in Britain nearly 

 50° ; in America 39°. This the author considers as strong, but not 

 new evidence against the theory of an ice-cap extending to low 

 latitudes ; the extent of the ice-cap would, of course, not be so wide 

 as that of the limits of glaciation,. owing to the floating ice approach- 

 ing nearer the equator. After commenting on Mr. Belt's remarks 

 made during the discussion of Mr. Campbell's paper, the author 

 states that he attributes the presence of the boulders found in the 

 valley of the Amazon to icebergs which had drifted further than 



