338 . PKOF. J. PKESTWICH ON THE EAISED 



time of deposition these [limbs] were partially united by ligaments." ^ 

 This may be so, though it has not been generally noticed, and, as a 

 rule, the bones are mingled together in the greatest confusion. All 

 of them belong to species which are found likewise in the Rubble- 

 drift and in the Coast Caves. 



Mr. Worth moreover refers to instances of the occurrence of 

 bones, supposed to be human, in the Ossiferous Breccia. Although 

 this wants confirmation, there can be no doubt about the probability 

 of finding human remains in this breccia, as Palaeolithic flint imple- 

 ments have been found in the E-ubble-drift at Portslade and at 

 Sangatte. There is, in fact, probably a better chance of finding 

 human bones in this association than in the implement-bearing 

 fluviatile deposits, inasmuch as, though man might have avoided 

 the partial floods of the rivers, he must have succumbed to the more 

 general effects of an extended submergence. 



I have given the reasons which lead me to suppose that the sub- 

 mergence was effected with extreme slowness, so as to disturb but 

 little the surface of the land. Under such conditions, the land- 

 animals would, as the waters rose, gradually retire to the higher 

 grounds of the district, and, when these sank below the level of the 

 flood, would be eventually drowned. Their bodies in some cases 

 may have been carried by currents to a distance and lost, and in 

 others they may have decayed and fallen in fragments to the bottom 

 without travelling far from the spot. Where they fell on an old 

 disintegrated land-surface, they would share with the debris in the 

 displacement and drifting which that debris afterwards underwent. 



Let us then suppose that, after a submergence of short duration, 

 the submerged land was again raised — not by one continuous 

 movement, but by a succession of uplifts more or less rapid, with 

 intervals of rest or of slow movement. This would produce, on the 

 slopes on all sides of the hills of the submerged area, divergent 

 currents which swept down the loose surface-debris with varying 

 rapidity and for varying distances. These uplifts, repeated at 

 indefinite intervals, led to the transport of successive portions of 

 detrital matter, which, when projected over the old clifis, was 

 carried forward to distances in accordance with the force of each 

 particular current. The successive layers of the Elephant Bed at 

 Brighton and Sangatte may be taken as indices of the varying force 

 of the currents, and consequently of the extent and rapidity of the 

 successive uplifts. They do not, however, owing to their lenticular 

 form and overlap, afford a true index of the number of uplifts, 

 which there is reason to believe were more numerous than indicated 

 in any single section. They vary in number in each of them, while 

 many beds have been disturbed and partially displaced by the force 

 of impact of the stronger shoots or throws. 



The volume of detritus carried forward would depend upon 

 various circumstances, such as the depth of water, angle and length 

 of slope, &c. Thus, if we take a range of hills (fig. 21), presenting 



1 Journ. Plymouth Inst. vol. vii. (1879) p. 109. 



