TRANSACTIONS OF SECTION C. 545 



siderable local climatic variations at the sea level since the Pliocene age. We 

 cannot, however, account in this way for the warmer climates of previous ages, but 

 must seek for their cause in the former constitution of the atmosphere. 



Touching the suggestion that former climatic changes were due to a displace- 

 ment of the earth's axis of rotation, the author expressed the opinion that it is 

 irreconcilable with the fact, long ago insisted upon by him, that " the direction 

 of the Arctic currents, which are guided by the earth's rotation, appears, from the 

 distribution of marine sediments, to have been the same since very early periods." 

 Dawson has reinforced this argument by recalling the fact that the southward mi- 

 gration of successive floras shows, in like manner, that from the Devonian age the 

 general courses of oceanic currents, and consequently the position of the earth's 

 axis, have not changed. 



6. Report of Committee on the Conductivity of Roclcs. 

 See Reports, p. 133. 



On the Saurians of the Dakota Cretaceous Roclcs of Colorado. 

 By Professor E. D. Cope. 



8. Notes on Eribollia Mackayi, a New Fossil from the Assynt Quartzite in 

 the North-Western Highlands of Scotland. By James Nicol, F.R.S.E., 

 F.G.S., Professor of Natural History in the University of Aberdeen. 



The remarkable fossils to which the above name has been given were found on 

 the western shore of Loch Eriboll by Mr. Donald Mackay, of Portnacow, in a por- 

 tion of the Assynt quartzite, or middle deposit of the west coast series of strata. 

 On a small block (of 9 inches by 7) more than a dozen peculiar bodies are seen 

 running down into the interior. They are mostly rounded and conical in form, and 

 show a central core, covering about half the width, and enclosed in an outer wall. 

 One of the most regular measures about 1£ inch above, and 3^- inches long to the 

 point below. Others are smaller, but similar in form and structure. Some of them 

 occur single, but others are joined in twos or threes, and arranged as if in 

 parallel rows. One of the largest, about 2 inches across, is more square in form, 

 and does not taper as it descends. 



The single conical forms much resemble Orthoceratites, but show no trace of 

 septse or partitions ; whilst the internal appearance and mode of grouping rather 

 Inclines the author to regard them as corals, approximating, in form at least, to 

 Cyathophyllidae. A similar fragment, found some years ago in the quartzite at 

 Ullapool, shows no structure when polished. As they differ very widely from any 

 known organism, he has named them Eribollia, from the locality, Maekayi, from 

 their discoverer. Some of the curious bodies, formerly described as casts of annelid 

 tubes may, he thinks, also prove similar corals. From the Ullapool quartzite he 

 has also a whorled shell (Macluria?). 



The author in conclusion stated that he still adheres to his published views of 

 the structure of the North-Western Highlands. 



9. On the Influence that Microscopic Vegetable Organisms have had on the 

 Production of some Hydrated Iron Ores. By M. Alphonse Gages. 



Geologists are aware of the influence some microscopic animal living organisms 

 have in the formation of bog ir^.n ore, resulting from the iron of surrounding decom- 

 posing rocks, and also of the properties that the skeletons of these organisms com- 

 municate to the iron. 



1878. N N 



