1 84 On Cyrtoma, a new genus of Fossil Echinida. 



Having gained about half the ascent, we found ourselves 

 on a narrow ridge which leads to a more precipitous part of 

 the road. It was here I found the first appearance of ter- 

 tiary fossils, and from a memorandum recently received from 

 Major Lister, I should suppose the altitude of the place 

 to be at least about 2,000 feet high. In a few hours I suc- 

 ceeded in raising as many specimens of marine shells as 

 I could convey. It was fortunate that I did so at once, as 

 I have never been able to revisit the spot. During the few 

 days we remained at Cherra Ponji, I made an excursion to 

 an opposite part of the declivity of the mountains, distant 

 probably ten or fifteen miles from the place at which I found 

 the fossils, and here at about the same elevation I came 

 again upon the organic belt, from which circumstance, as 

 well as the nature and character of the organic remains, the 

 presence of a raised beach could no longer be questioned, 

 although several hundred miles from the sea, as well as 

 several thousand feet above it. As the Assam deputation 

 had to proceed on its journey the following morning after 

 this further discovery was made, I can give little infor- 

 mation more than an accurate description of the fossils 

 obtained, and a few general remarks on the circumstances 

 under which they are found.* In the first situation the re- 

 mains were such as are usually found in sheltered sea coasts, 

 subject to the ebbing and flowing of tides. In the second situa- 

 tion, which lies at least 12 miles to the north-west of the first, 

 and consequently so much further from the sea, the animals 

 most abundant are Echinida, which in a living state are 

 chiefly found on the exposed open rocky coasts of islands 

 and promontories, and never in estuaries or sheltered situa- 



* Very copious geological notes weve kept during this part of the journey to 

 Assam, which I may have occasion to refer to in future papers on the Cherra 

 fossils, should no opportunity offer for collecting better information on this interest- 

 ing subject. 



