212 FLUVIO-MARINE SEEIES IN" HAMPSHIRE. [Ch. XVL 



Among the chelonians we find a species of Emys, and no less than six 

 species of Trionyx ; among the saurians an alligator and a crocodile ; 

 among the ophidians two species of land-snakes (Paleryx, Owen) ; and 

 among the fish Sir P. Egerton and Mr. Wood have found the jaws, teeth, 

 and hard shining scales of the genus Lepidosteus or bony pike of the 

 American rivers. This same genus of freshwater ganoids has also been 

 met with in the Hempstead beds of the Isle of Wight. The bones of 

 several birds have been obtained from Hordwell, and the remains of quad- 

 rupeds. The latter belong to the genera Paloplotherium of Owen, Ano- 

 plotherium, Anthracothe?ium, Dichodon of Owen (a new genus discovered 

 by Mr. A. H. Falconer), Dichobune, Spalacodon, and Hycenodon. The 

 latter offers, I believe, the oldest known example of a true carnivorous 

 mammal in the series of British fossils, although I attach very little the- 

 oretical importance to the fact, because herbivorous species are those most 

 easily met with in a fossil state in all save cavern deposits. In another 

 point of view, however, this fauna deserves notice. Its geological position 

 is considerably lower than that of the Bembridge or Montmartre beds, 

 from which it differs almost as much in sj)ecies as it does from the 

 still more ancient fauna of the Lower Eocene beds to be mentioned 

 in the sequel. It therefore teaches us what a grand succession of distinct 

 assemblages of mammalia flourished on the earth during the Eocene 

 period. 



Many of the marine shells of the brackish-water beds of the above 

 series, both in the Isle of Wight and Hordwell Cliff, are common to the 

 underlying Barton clay ; and, on the other hand, there are some fresh- 

 water shells, such as Cyrena obovata, which are common to the Bem- 

 bridge beds, notwithstanding the intervention of the St. Helen's series. 

 The white and green marls of the Headon series, and some of the accom- 

 panying limestones, often resemble the Eocene strata of France in mineral 

 character and color in so striking a manner, as to suggest the idea that 

 the sediment was derived from the same region or produced contempo- 

 raneously under very similar geographical circumstances. 



Both in Hordwell Cliff and in the Isle of Wight, the Headon beds rest 

 on white sands, the upper member of the Barton series, B. 4, next to be 

 mentioned. 



Headon Hill sands and Barton clay, B. 4 (Table, p. 208). — In one of 

 the upper and sandy beds of this formation Dr. Wright 

 found Ckama squamosa in great plenty. The same sands Fl &- 197 - 



contain impressions of many marine shells (especially in 

 Whitecliff Bay) common to the upper Bagshot sands 

 afterwards to be described. The underlying Barton clay 

 has yielded about 209 marine shells, more than half of 

 them, according to Mr. Prestwich, peculiar; and only 

 eleven common to the London clay proper (C. 1, p. 208), 

 being in the proportion of only 5 per cent. On the other 

 hand, 10 of them agree with the shells of the calcaire 

 .grossier of France. It is nearly a century since Brander published, in 



