C— GEOLOGY 75 



a multiple succession of glacial deposits. The deposits filling the 

 Kirmington Channel were investigated in detail by a British Association 

 Committee. The report of the Committee showed that the Purple 

 Boulder Clay of the district (known from sections farther north in York- 

 shire to be due to a later glaciation than the Scandinavian Drift) was 

 succeeded first by sand, then laminated silts with estuarine shells and 

 containing peat with marsh plants and fresh-water shells, next gravel, 

 and, finally, ' Hessle ' Boulder Clay. The plants indicated a sub-arctic 

 climate ; the estuarine shells recorded were Cardmm edule and Scrobi- 

 cularia ptperata. The ' Hessle ' Boulder Clay here is that of inland 

 sections and is apparently not the equivalent of that of the coast-sections, 

 which is to be correlated with the Brown Boulder Clay of Hunstanton. 

 The sands, silts and gravels may thus correspond to similar beds at Hoxne. 

 The Purple Boulder Clay has usually been regarded as the time-equivalent 

 of the Great Chalky Boulder Clay west of the Lmcolnshire Wolds, a 

 deposit which continues into the Eastern Counties as the Chalky-Jurassic 

 and Chalky-Neocomian Boulder Clay, but the possibility of there being 

 two Purple Boulder Clays must be borne in mind. The correlation of 

 the Kirmington series with our standard succession will be open to 

 doubt until the laminated silts or associated beds yield implements. 

 Mr. J. P. T. Burchell's recent discovery of Early Mousterian (Clactonian) 

 implements in the ' Hessle ' Boulder Clay ( = ? the Upper Purple Boulder 

 Clay) of Kirmington is of great interest, for it suggests that the Purple 

 Boulder Clay at the base of the Kirmington series is the Lower Purple 

 Boulder Clay, a conclusion confirmed, in his opinion, by its petrographic 

 characters. Although Corbicula fluminalis has not been found at Kirm- 

 ington, it is recorded in gravels above a Purple Boulder Clay elsewhere 

 in northern Lincolnshire. 



Yorkshire. 



So graphic a word-picture of glacial conditions in Yorkshire has been 

 painted by Messrs. Kendall and Wroot that I need only refer to their 

 book on The Geology of Yorkshire and recall that, as in East Anglia, 

 a succession of at least three definite Boulder Clays has been established : 

 the lowermost or Basement Clay containing numerous Scandinavian 

 erratics, the Purple Clays (the ' Middle Series ' of Mr. J. W. Stather), 

 and the Hessle Clay. Each has its special characters, and these throw 

 light on its origin and on the course of the ice-movement. Unlike East 

 Anglia, however, no datable interglacial faunas and floras have been found, 

 and no very definite traces of Early Palaeolithic Man. The relationships 

 of the one implement obtained (of Acheulian type, from near Huntow) 

 are obscure. What are claimed to be implements in chert, of supposed 

 Early Chellian age, have recently been discovered in the moraines, and 

 on the Moors, of Nidderdale. The sketches of these unabraded rock- 

 fragments are unconvincing to a geologist, but if the workmanship is 

 accepted by archzeologists, the occurrence of relatively unabraded Early 

 Chellian or even Mousterian implements in such late-glacial deposits 

 associated with retreat-phenomena seems to upset our tentative sequence. 

 Discoveries by Mr. J. P. T. Burchell of Aurignacian implements near 



