72 Microscopical Society, 



Marine erratic gravel with flints. — These accumulations commence 

 immediately south of the Avon. The village of Bredon stands on a 

 platform, seventy feet above the ordinary level of the Avon, com- 

 posed of lias with an uneven surface, and capped with 10 to 15 

 feet of this gravel. It contains no mammalian remains. 



Fluviatile gravel. — The only example of this drift, on the line of 

 the railway, occupies the two opposite flanks of the Avon at DefFord 

 and Eckington, north of Bredon. At these localities the surface is 

 a tabular platform which does not exceed forty-five feet above the 

 Avon, including a capping of ten feet of gravel precisely similar to 

 the flinty gravel of Bredon, but containing abundance of mammalian 

 remains. They were chiefly found in the cutting north of Ecking- 

 ton, at the lower part of the deposit, and often on the surface of 

 the lias clay ; and are referrible to Elephas primigenius, Hippopotamus 

 major. Bos Urus, and Cervus giganteus } On the north, or Defibrd 

 side of the Avon, the remains of Elephas primigenius and Rhinoceros 

 trichorhinus have been obtained. Associated with these bones are 

 numerous freshwater shells, agreeing with those found at Crop- 

 thorne *; the most abundant species being Cyclas amnica and C. 

 cornea. In endeavouring to account for the presence of these re- 

 mains at only one point in the line of the railway, Mr. Strickland 

 states that he can off^er no other explanation than that previously 

 proposed by him f, namely, that after the beds of marine gravel had 

 been deposited and laid dry by the elevation of the land, a large 

 river or chain of lakes extended down the valley of the Avon, at a 

 height varying from twenty to fifty feet above its present course ; 

 and that the gravel previously accumulated by marine currents, was 

 remodified by the river, and mixed up with remains of mammalia 

 which tenanted its banks, or of moUusca which inhabited its waters. 



Local gravel — This species of detritus occurs abundantly at Chel- 

 tenham, and consists exclusively of detritus from the oolites and lias 

 of the vicinity. No bones or terrestrial remains have been found in 

 it ; and, therefore, the author assigns to it, in the absence of other 

 evidence, a marine origin. 



Modern alluvia. — The only deposits of this nature mentioned in 

 the paper, are the peaty accumulations on the banks of the Avoi^ 

 and its tributaries. 



The memoir was accompanied by a copy of the Railway Section, 

 and of the Tewkesbury branch, and the junction branch from the 

 main line to the London and Birmingham Railway, presented by 

 Capt. Moorsom, but coloured geologically by Mr. Strickland. 



MICROSCOPICAL SOCIETY. 



Jan. 27, 1841. — Richard Owen, Esq., President, in the Chair. 

 A paper was read by Mr. Bowerbank, " On the Keratose or Horny 

 Sponges of Commerce." 



The author, after noticing the labours of Dr. Grant and Dr. Fle- 



* Silur. Syst., p. 555 ; and Proceedings, vol. ii. pp. 6 and 95. 

 t Reports of British Association, vol. vi. Sections, p. 64. 



