556 



DEPOSITS OF THE ANCIENT AVON. 



I examined in company with him two of the sections to which he refers. The clearest 

 of these is at Bricklehampton Bank, near Cropthorn on the Avon, where about 20 feet 

 of this detrital matter is arranged in the following manner resting upon the lias clay. 



Upper portion, stiff reddish clay with a few pebbles ; the central also argillaceous but more marly, of green and purple 

 colours, with some yellow sand and occasional irregular laminae of marl ; lowest, sand and gravel confusedly mixed up 

 with lumps of marl, pebbles of quartz (some 5 to 6 inches in diameter), broken chalk flints, much detritus of the lias, and 

 very rarely a fragment of oolite. 



Many of the delicate shells mentioned in Mr. Strickland's list, were found from the 

 top to the bottom of this varied, and almost coarse drift ; being just as abundant in the 

 underlying gravel as in the overlying marl and clay. The bones of the quadrupeds oc- 

 curred also through the mass, though they were most abundant in the lower part. The 

 discovery of these fragile shells, perfectly preserved in beds of such coarse and irre- 

 gularly formed detritus, is of importance, as it proves that much of the gravel to which 

 the term " diluvium" has been applied, may have been deposited by rivers. 



It is thus evident, that these fluviatile materials were drifted by a river which flowed 

 through dry land on the E.N.E. into the channel or estuary so often mentioned ; and it 

 is therefore probable, that they were sometimes transported beyond the mouth of the 

 ancient Avon, and deposited in shoals or banks beneath the waters of the channel. 



The bones of extinct quadrupeds, already noticed as occurring on the western or op- 

 posite side of the valley of the Severn, at Powick and Bromwich Hill near Worcester, 

 and at Fleet Bank near Sandlin 1 , were probably at once washed into the ancient estuary 

 from the adjoining hills by sudden and local floods, as they are not imbedded in debris 

 similar to that of the Avon. The physical features of the country marked by the narrow 

 ridge of the Malverns impending over the valley, account, indeed, for the non-existence 

 of former rivers, and consequently of fluviatile shells in this direction. 



But were all these extinct terrestrial remains deposited in gravel when the marine 

 shells were living in the sea ? In answering this question it might be argued, that the 

 great mass of the fluviatile and land shells are of existing species, and that the few 

 which are supposed to be lost, may possibly still exist and have escaped the research of 

 naturalists. On the other hand it might be said, though all the marine shells we have 

 yet discovered associated with northern drift, appear to belong to existing species, other 

 shells may yet be found which are extinct. The sea shells of the marine drift, and the 

 fluviatile shells of the Cropthorn gravel, may therefore have coexisted. But are we to 

 explain this Avon deposit by the hypothesis of pure fluviatile action, after the bed of the 

 adjacent straits had been partially raised, or shall we suppose that the marine gravel 

 on the adjoining hillocks, formed the shallow subaqueous banks of an estuary through 

 which the mouth of the Avon then found its way to the sea ? Adopting the first of these 



1 Through the kindness of the members of the Worcestershire Natural History Society, I procured a large 

 suite of the animal remains found in these localities, and submitted it to Mr. Clift, Curator of the Museums 

 of the Royal College of Surgeons, who informs me, that the bones belong to extinct species of hippopotamus, 

 rhinoceros, elephant, stag and ox. 



