1870.] WHITAKER SOUTH DORSET AND DEVON CHALK, 97 



until we pass the border of Dorsetshire, just beyond Lyme Eegis, and 

 enter Devonshire, where the high cliifs are broken by the great range 

 of landslips that add so much to their beauty. The sections here 

 have been described by Sir H. De la Beche * ; and from his account 

 of the Chalk seen near Lyme it appears that the lower, or flintless, 

 division is thin, having a thickness indeed of not more than 40 feet, 

 whilst the lowermost 50 feet of the Upper Chalk contains fewer flints 

 than the overlying part, in which they are frequent. I cannot un- 

 derstand, though, how so great a thickness as 20 feet is given by 

 him to the Chalk with quartz -grains, unless, as seems likely, the 

 whole of the Chalk Marl is therein included. 



In the Chalk with flints at Pinhay t &c. there are brown hard 

 nodular layers, weathering to a rough surface, as at "White Nore, east 

 of Weymouth. In the undereliff fallen masses show the junction of 

 the Chalk and the Greensand, the bottom of the former consisting of a 

 hard buff nodular bed, with dark grains and quartz-grains, from 2 

 to 3 feet thick, above which, for from 2 to 4 feet, the Chalk has irre- 

 gular masses of the same brown nodular character, and also the 

 distinctive grains. Here, indeed, it is often hard to mark the junc- 

 tion ; the Chalk gets nodular, darker, and harder, until it seems 

 almost one mass with the Greensand. 



Near the cliff-top just east of Charton, the junction may be seen 

 in place, the same two beds occurring, and the upper of them passing 

 up into white chalk with hard brownish nodular lumps, which (8 

 or 10 feet above the greensand) form a projecting bed about 1| 

 foot thick. Some of the quartz-grains here are larger than those in 

 the country to the east. 



At the western end of the Dowland's landslip the bottom six 

 feet of the chalk are hard, quartz-grains occur therein, and the 

 lower part is slightly darker and compact. 



At the mouth of the Axe the bed with quartz-grains is about 

 three feet thick and contains fossils. 



The section near Beer has also been described by Sir H. De La 

 Beche ; but something may be added to his account. The chalk- 

 with-flints of White Cliff contains hard buff nodular layers (as else- 

 where), and its bottom part has fewer flints than the rest. The 

 chalk without flints also contains hard nodular layers, and is of 

 comparatively small thickness, perhaps thirty feet ; the lowermost 

 three feet or so are the same as to the east. 



Westward of Beer Head the bold cliffs, here separated from the 

 sea by a fine undereliff, give a most interesting section, part of 

 which shows a thinning-out of the Lower Chalk, and consequently 

 the direct superposition of Upper Chalk on Upper Greensand — an 

 occurrence which I believe has not been before noticed in this country. 

 This junction is inaccessible, and can be seen only from below, and 

 then, from the roughness of the cliff, not with the greatest ease. 

 In fig. 2 it has been thrown into the form of a diagram, as it would 



* Trans. Geol. Soc. ser. 2, vol. ii. p. 110, and " Eeport on the Geoloay o£ 

 Cornwall, Devon, and West Somerset," p. 237- 



t Pinney on the Ordnance Map. 

 VOL. XXVII. PART I. BL 



