Vol. 59.] THE BOULDER-CLAY AT BIGGLESWADE. 381 



propounded two quite distinct questions for consideration. In the 

 first place came the precise stratigraphical horizon of the strata which 

 had been described, and the characters of the fossils which they had 

 yielded. On these points, which were essentially palgeontological, 

 the evidence was so clear that little room was left for differences of 

 opinion. In the second place, a fresh and interesting example had 

 now been added to those already known of large ' cakes ' of Mesozoic 

 strata which had been transported to greater or less distances during 

 the Ice-Age. The precise process by which this transport had been 

 effected still remained to be satisfactorily explained. The speaker 

 found some difficulty in conceiving that such extensive and, com- 

 pared with their superficies, thin sheets of soft strata could be 

 ploughed out and pushed forward by the ice-sheet. On the other 

 hand, while ' cakes ' of flat strata in situ might be frozen into shore- 

 ice and be carried off to other parts of a region, it was not quite 

 easy to realize the conditions in which this mode of removal could 

 have occurred in the case of such huge masses as had now been 

 recognized to be unquestionably erratic. In the meantime, it was 

 important to gather all the available evidence, each addition to 

 which might help to clear away a little of the obscurity of the 

 problem. As a contribution towards this end, the present paper 

 was welcomed by the Society. 



The Author said that he was very much indebted to the 

 Fellows for the kind way in which they had received his paper. 

 In reply to Mr. Hudleston, he suggested that the thinness of the 

 Gault in this section might be due to its having been ploughed 

 away by the Glacial Boulder-Clay. He hoped to be able to 

 find out something more, in regard to the area of this boulder, in 

 future excavations. 



