370 Geological Society : Prof. Owen's Description 



Everest's journey, and he was prevented from examining the locality 

 which produces the Ammonites and other fossils obtained by Dr. 

 Gerard ; but he believes, from the information supplied by the natives, 

 that they are met with abundantly beyond the frontier, imbedded 

 in black compact limestone and earthy carbonaceous shale. Mr. 

 Everest further states, that since his journey Captain Hutton has 

 discovered them within the frontier. 



In the course of the memoir the author mentions having seen at 

 Seenum the skin of a " leopard " recently killed near the village, 

 though large quantities of snow were then (May) lying upon the 

 ground, and that he has frequently observed in February and March 

 their tracks on the snow as high as the limit of the forests. He 

 also states that he has observed monkeys at the height of full 8000 

 feet above the sea in the same months when the ground was co- 

 vered deep with snow, feeding in great numbers on the seeds of the 

 fir cones. 



A paper was afterwards read containing a " Description of the Re- 

 mains of Six Species of Marine Turtles (Chelones) from the London 

 Clay of Sheppey and Harwich." By Richard Owen, Esq., F.R.S., 

 F.G.S., Hunterian Professor in the Royal College of Surgeons. 



The author commences by quoting the generalizations given in 

 the latest works which treat of Fossil Chelonians, and examines the 

 evidence on which those from the Eocene day of Sheppey had been 

 referred exclusively to the freshwater genus Emys by Cuvier and 

 others, and he points out the circumstances which invalidate the 

 conclusions that had been deduced from it. He then proceeds to 

 describe the fossils and to show the characters by which he has 

 established the existence of five species of marine turtles from the 

 London Clay at Sheppey, and a sixth species from the same forma- 

 tion near Harwich. 



1 . Chelone breviceps. — The first species, found at Sheppey, is called 

 by the author Chelone breviceps, and its unequivocal marine nature 

 was recognised by a nearly perfect cranium, wanting only the occipital 

 spine, and presenting a strong and uninterrupted roof, extended 

 from the parietal spine on each side over the temporal openings ;, the 

 roof being formed chiefly by a great development of the posterior 

 frontals. Further evidence of its marine origin exists in the large 

 size and lateral aspect of the orbits, their posterior boundary extend- 

 ing beyond the anterior margin of the parietals ; also in the absence 

 of the deep emargination which separates the superior maxillary from 

 the tympanic bone in freshwater tortoises, especially the Emys 

 expansa. 



In general form the skull resembles that of the Chelone Mydas, but 

 it is relatively broader, the anterior frontals are less sloping, and the 

 anterior part of the head is more vertically truncate : the median 

 frontals also enter into the formation of the orbits in rather a larger 

 proportion than in C. Mydas. In Chelone imbricata they are wholly 

 excluded from the orbits. 



The trefoil shape of the occipital tubercle is well-marked; the 

 laterally expanded spinous plate of the parietal bones is united by a 



