348 P^'f]f' Sedgwick on th^ [May, 



be traced, generally near the base of the escarpment, and sur- 

 mounted by ruinous masses of argillaceous marl. In sinking a 

 well for the use of the barracks near Newport, they are said to 

 have brought up from the depth of 265 feet some specimens of 

 green marl containing fossils exactly resembling some of those 

 which abound at the foot of Hampstead Chff. 1 am in posses- 

 sion of one of these specimens, which, if its locality be correctly 

 given, almost proves that the lower freshwater formation ex\^i& 

 in some places near Newport about 260 feet below the surface. 

 An examination of the old cabinets of Dr. Woodward had long 

 since led me to expect that very important traces of the fresh- 

 water formations would be found on the Hampshire coast ; but 

 I had never, before last July, an opportunity of verifying the 

 conjecture. After an excursion made by Mr. Whewell and 

 myself to the neighbourhood of Christchurch, we returned by 

 the Barton and Hordwell cliffs. This enabled us to observe the 

 first appearance of the London clay, its termination in the cliff 

 between the villages of Barton and Hordwell, and the beds of 

 marine sand which succeeded, as we have already mentioned. 

 The existence of a freshwater formation, extending nearly 

 through the whole of Hordwell Cliff, was certainly more than 

 we had ventured to anticipate. Any minute details which we 

 might offer respecting this part of the coast would be received 

 with distrust, as we lost nearly all the specimens we collected 

 from it; and the attempt would be unnecessary, as Mr. Webster 

 has subsequently undertaken the description of it. We shall, 

 therefore, content ourselves with stating, that the formation 

 which succeeds the marine sand above-mentioned is composed 

 of various coloured beds of sand, loam, carbonaceous clay, argil- 

 laceous and calcareous marl seldom in a state of induration, 

 several carbonaceous beds, some of which are three or four feet 

 thick, 8cc. &c. All these beds are succeeded by some thick 

 beds of bluish argillaceous marl, which are prolonged to the east, 

 and at length carried, by the natural dip of the strata, under a 

 cliff of diluvian gravel. Among the characteristic fossils may 

 be enumerated the following : 



(1.) Planorbis. 



(2.) Li/mncea. 



(3.) F'uludina. 



(4.) A small bivalve which resembles mya; it exists in immense 

 abundance in the freshwater formations of the Isle of Wight. 



(5.) Melunopsis, 



(6.) Cyclas. 



(7.) Vnio. 



(8.) Potamides, 8cc. &c. 



We found, however, several cerithia, and some other shells 



which we at the time considered of marine origin. From this 



circumstance we were disposed to regard the great deposit of 



^Hordwell Cliff as the representative both of the lower freshwater 



