442 Dr. T. Wright on the Freshwater and Marine 



A very perfect specimen of a Turtle was discovered in this bed 

 with the carapace and plastron well preserved, but it fell to 

 pieces on being removed from the sand. We collected fragments 

 of the bones of Cheloni<s, and teeth of Lamna and Myliobiitis. 

 The gray sand measures about 5 feet, and passes gradually into 

 No. 17, of which it may be considered to form the upper fos- 

 siliferous portion. 



No. 17. Fine white sand ; non-fossiliferous : rises on the shore 

 about half a mile east of Beacon Bunny, and disappears beyond 

 Barton Gang. As it passes through Barton Cliff it becomes of 

 a light sulphur-colour, streaked with darker shades, and forms a 

 conspicuous portion of the section, which, when lit up by the 

 sun's rays, presents a beautiful picturesque effect from the water : 

 it measures from 15 to 20 ft. 



Nos. 16 and 17 were unquestionably an estuary deposit, as 

 proved by the list of fossils contained therein ; from their stra- 

 tigraphical position in the series they are the equivalent in 

 the Hampshire section of the Headon Hill sands of Alum and 

 White Cliff Bays in the Isle of Wight. We attach therefore 

 much importance to the analysis of the organic remains they 

 contain, as it throws considerable light on the conditions under 

 which the Headon Hill sands were deposited. 



The shelly fragments contained in the latter beds are in such 

 a broken and rounded condition that it is impossible to decide to 

 what genera they belong. In my paper on the Isle of Wight 

 it was observed in reference to these beds, that " the white and 

 yellow sands at Alum Bay, immediately overlying the Barton 

 group, were probably of estuary origin. The absence of organic 

 remains leaves a doubt upon the subject. The equivalent bed 

 however at Beacon Cliff on the Hampshire coast, which shall be 

 more particularly described in a future commimication, contains 

 a large quantity of estuary shells mixed with true marine genera, 

 together with the bones of turtles and the teeth of sharks." 

 Guided by these facts, we infer " that the white and yellow sands 

 of Headon Hill were the great estuary deposit which introduced 

 the lacustrine conditions under which the lower freshwater group, 

 with the other intercalated estuary beds, were deposited." 



The Lower Marine Formation. 



No. 18. Tea-green coloured clay; rises on the shore near 

 Mead End, about a quarter of a mile east of Beacon Bunny, and 



