Geoloyical Society. 71 



minima, and a coral. At Abbot's Wood the fissile sandstone at the 

 base of the lias is again exposed, having been brought up by a fault. 

 At Defford and Eckington the lias clay encloses numerous speci- 

 mens of Pachyodon Lister i (Stuchbury), or Unio Listeri of Sowerby, 

 and Ammonites Titrneri. At Bredon a higher portion of the lias 

 series was reached, and a different suite of fossils found, the most 

 marked being Pleurotomaria Anglica, Hippopodium ponderosiim, Gry' 

 phcca incurva. Nautilus striatus, and several species of Ammonites. 

 Between Cheltenham and Gloucester the lias has yielded great 

 abundance of organic remains, a considerable number of which are 

 considered to be new, and with the exception of Hippopodium pondero- 

 sum, Gryphcea incurva, and one or two others, they are distinct from 

 the fossils of Bredon Hill ; and at Hewlitt's, east of Cheltenham, the 

 lias near the base of the marlstone presents another series of distinct 

 fossils. The lower lias, therefore, Mr. Strickland observes, affords 

 evidences of at least four well-marked successions of molluscous 

 faunae, in a vertical height of 400 or 500 feet, and unaccompanied 

 by any change in the mineral character of the deposits. 



Superficial detritus. — The author then proceeds to describe the 

 deposits of superficial detritus, and he states, that they entirely con- 

 firm the views which he had previously entertained, respecting the 

 distinction between the ancient terrestrial alluvia in which bones of 

 mammalia occur, and the submarine drift which covers most parts 

 of the island*. 



He divides the detritus into fluviatlle and marine, and the latter, 

 according to its origin, into local and erratic, and this, according to 

 its composition, into gravel with flints and without flints. 



Marine erratic gravel without flintsf. — Commencing his details with 

 the Birmingham end of the line, Mr. Strickland shows, that these 

 accumulations occur extensively on all sides of that town, and at in- 

 tervals along the line of the railway till it approaches the valley of 

 the Avon. Mammalian remains appear to be totally wanting. 

 Chalk flints are so extremely rare in it around Birmingham as to 

 prove that the materials were transported from the north. At 

 Mosely it is upwards of 80 feet thick, and consists of rolled pebbles, 

 rarely exceeding 4 inches in diameter, of various granitic and 

 quartzose rocks and altered sandstones, imbedded in a clean ferru- 

 ginous sand ; and a bed of sand 30 feet thick, without pebbles, 

 occurs in the middle of the gravel. Between Cotteridge and Wytch- 

 all is an erratic boulder, or shapeless mass of porphyritic trap, 

 about 5 feet by 4, with the angles slightly rounded. At the Lickey, 

 gravel analogous to that near Birmingham, but with a large pro- 

 portion of slate rocks, attains, on the line of the railway, a height of 

 387 feet, and at the Lickey Beacon of more than 900 feet. Sugar's 

 Brook is the next locality noticed by Mr. Strickland, but from that 

 point no gravel occurs for sixteen miles. Near Abbot's Wood is 

 another extensive deposit of quartzose gravel and ferruginous sand, 

 devoid of flints and resting upon lias. 



* See Reports of the British Association, vol. vi.. Sessional IMectings, 

 p. 61. 



t Northern drift of Mr. Murchison, Silur. Syst,, p. 523. 



