230 Reports and Proceedings. 



inquire whether the colour might not he derived from the decomposition of rocks 

 composed of hornblendic materials. The Old Red Sandstone beds, though in this 

 country containing fishes which might be of fresh-water genera, had in Eussia the 

 same fishes associated with marine shells ; and much the same was the case in the Trias. 



Dr. Carpenter had been led to the conclusion that wherever there was an inland 

 sea connected with the ocean by a strait even of moderate depth there was a double 

 current tending to preserve some degree of similarity between the waters of the two, 

 the difference of specific gravity in the Mediterranean as compared with the Atlantic 

 being about as 1-026 to r'029. In the Red Sea, where so little fresh water came in, 

 and there was an evaporation of nearly eight feet per annum, the water was but little 

 Salter than that of the ocean with which it was connected. In the Baltic there is an 

 undercurrent inwards, which still keeps it brackish ; for otherwise the influx of fresh 

 water was so enormously in excess of the evaporation, that it would long ago have 

 become perfectly fresh. Such facts bore materially on the speculations of the author. 



Capt. Spratt maintained that in the Dardanelles there was not a trace of such an 

 undercurrent as mentioned by Dr. Carpenter, In the winter months, when the flow of 

 the rivers into the Black Sea was for the most part arrested by ice, the salt water of the 

 Mediterranean was carried into the inland seas, and these being much deeper than the 

 channel of the Dardanelles, the salt water, by its greater specific gravity, remained in 

 the bottom of the sea of Marmora, so that while the upper portion of the water and 

 that on the shores were fresh, marine conditions existed in the deep centre of the sea. 



Dr. Duncan mentioned that in certain coral reefs intersected by freshwater cur- 

 rents, the corals still continued to be formed ; so that the existence of dwarfed forms 

 of corals in ancient times was quite consistent with modern facts. 



Mr. Forbes commented on the chemical features of Prof. Ramsay's views, and 

 could see no reason why the beds containing iron should not have been deposited in 

 the open sea. Many beds, for instance the Gault, contain more iron than those 

 which are now red, though they may be grey or blue. In sands the grains are often 

 coloured only superficially with iron, probably derived from sulphates. In other 

 cases the sands consist of fragments of rocks already red. There was, in fact, no 

 reason why the beds deposited in the open sea might not subsequently, by oxidation, 

 become perfectly red. 



Prof. Ramsay replied to the remarks of the various speakers, and summed up by 

 contrasting the usual colour of marine fossiliferous beds with that of the thick, almost 

 non-fossiliferous rocks of which he had been treating. 



II. March 22Tia, 1871.— Prof. John Morris, Vice-President, in the 

 Chair. The following communications were read: — 1. "On the 

 ' Passage- beds ' in the neighbourhood of Woolhope, Herefordshire, 

 and on the discovery of a new species of Em-ypterus, and some new 

 Land-plants in them." By the Eev. P. B. Brodie, M.A., F.G.S. 



The author described as the '' passage-beds " between the Silurian 

 and Old Eed Sandstone formations near Woolhope, a series of shales 

 and sandstones, which at Purton attain a thickness of about 17 feet. 

 Here the section includes, in descending order : 1. Thin-bedded 

 sandstones ; 2. Dark brownish shales ; 3. Yellow Sandstone ; 4. 

 Olive shales ; 5. Thin-bedded sandstone ; 6. Olive shales, similar to 

 No. 4. At some localities vegetable remains (Lycopodites, and per- 

 haps Psilophyton) occur in the olive shales, which also contain 

 several Crustacean fossils, including Pterygotus Banksii and a new 

 species of Eurypterus, named by Mr. Henry Woodward E. Brodiei. 

 Upon this species Mr, Woodward presented a note supplementary to 

 Mr. Brodie's paper. 



Discussion. — Dr. Duncan inquired whether any metamorphoses had been re- 

 cognized among the Eurypteridaj, and, if so, whether the variation in the thoracic 

 plates mentioned by Mr. Woodward might be connected with them. 



Mr. Woodward, in reply, remarked on the difficulty of distinguishing the sexes in 



