188 Correspondence — C. E. de Ranee. 



" Formby and Leasowe Marine-beds" for the deposits below the peat, 



which it is impossible for me. to do — firstly, because he inclutles the 



Middle Glacial Sand and Shingle with the Postglacial Shirdley 



Hill Marine Sand, which I found to rest on thin seams of peat ; 



secondly, because I consider his Marine-beds to be estuarine and 



lacustrine; and thirdly, because the names I proposed in 1869 for 



these beds have the priority of age, his paper appearing in 1872. 



In my paper on the Post-glacial Deposits of Western Lancashire 



and Cheshire (Quart. Journ. Geol. Soc, 1870), in the Explanation of 



the Geological Survey Map 90 S.E., in 1870, in that of 90 N.E., 



1872, and in the Explanation of the Geological Survey Horizontal 



Section, Sheet 63, 1 have described the following sequence of Drifts : 



f /■ Blowing Sand, Blown Sand (Land-surface). 



Eecent I ^PP*^^' " Cyclas" Clay. ) ah,,,,,-,,™ 

 I ^^^'^^^'^ Sand and Loam. \ A^'uvium. ^^^^^^ 



Fost- Tertiary.'!^ \ Upper " Scrobicularia Clay " — Tidal Alluvial Estua- 

 I [ Upper Peat, often 20 to 30 ft. in thickness (Land- 



I Pre-historic \ Lower Cyclas Clay (Lacustrine). ) [surface). 



l^ ( Lower " Scrobicularia Clay" (Tidal). \ 



f Post p'lao" I \ ^^i^'^l^y Hill Sand, Presall Shingle (Marine). 

 I '^ I Lower Peat (Land Surface). 



Newer ) ( Upper Boulder Clay (Marine). 



Pliocene. \ r-j „• i ) Middle Sand and Shingle (Marine). 

 I \ Lower Boulder Clay (Marine). ) 



t. ( Till (Land -surface). \ 



In 1868, after reading Mr. Morton's description of the thick peat 

 beds resting on Scrobicularia Clays, exposed on the coast of Wirral, 

 near Leasowe, I visited that district, and correlated his Scrobicularia 

 Clay with a like clay occurring at Eccles Place, near Crossens, in the 

 estuary of the Eibble, the overlying thick peat being nearly con- 

 tinuous between the two points. Finding another clay with Scro- 

 bicularia in the alluvium of the Alt, of later date than the peat, I 

 described it in the " Explanation of the Geological Survey Map 90 

 S.E.," as the "Upper Scrobicularia Clay," in contradistinction to the 

 Lower Scrobicularia Clay of Wirral and Crossens, which latter 

 deposit, though recognized to the north and south of the area com- 

 prised in that Map, I failed to find in that area, after a most careful 

 examination of all the grey clays thrown out, in cutting the long 

 dykes and sluices so characteristic of that country. Here and there, 

 at isolated points, as immediately east of Freshfield and Ainsdale, in 

 the experimental brick pit made near the "Isle of Wight," Birkdale, I 

 found shells of Cyclas cornea, fragments of horns of red deer, and 

 thin seams of peat. 



I therefore am convinced that the larger portion of these clays in 

 Lancashire, but not in Cheshire, or in North Wales, are of fresh- 

 water origin. But at the same time, from their gradual thinning out 

 eastward upon marine Shirdley Hill Sand,' from the intercalation of 

 the " Tellina Balthica Sand," in the main peat of Crossens and 

 Leasowe, and from the similar intercalation of peat in the grey clays 



' As shown in Hor. Sec. of the Geol. Sur., Sheet 63, and described in its Explana- 

 tion, and in the Exp. of Geol. Sur. Map 90 S.E., 1870.— C. E. De R. 



