328 PREHISTORIC EUROPE. 



are so clearly evinced by the great breccias of Gibraltar. The 

 following, for example, is the summary of the section exposed 

 by Dr. Adams in the Benghisa Gap, a narrow, steep-sided gully 

 or trench eroded in calcareous sandstone, which he found com- 

 pletely filled up with sundry deposits and accumulations. The 

 section is given in its natural sequence, from above downwards : — 



1. White calcareous drift, with scattered fragments of sandstone ; 



shows faint traces of bedding ; six or eight feet thick ; no 

 organic remains. 



2. Layer of pebbles and red soil. 



3. Layer of rounded blocks of freestone, some measuring fifteen feet 



in circumference, with abundant remains of Pleistocene mam- 

 mals (pigmy elephants, huge freshwater turtle, gigantic dor- 

 mouse, lizards, birds, etc.) 



4. Rich ferruginous red loam ; not laminated ; a few pebbles and 



freestone-blocks intermixed. 



5. Layer of gravel and rounded waterworn freestone-pebbles. 



6. Large blocks of the parent rock, mixed pell-mell with red soil and 



silt ; occupies the bottom of the " Gap ; " mammalian remains. 



Of this section Dr. Adams says — It " displays several dis- 

 tinct alternations of bands of large waterworn blocks and seams 

 of loam and pebbles, representing periods of turbulence and of 

 comparative quiescence, such as would result from violent floods 

 or freshets pouring down a gorge. I found the elephantine re- 

 mains identical in every respect with those already mentioned. 

 Be it observed, however, that no organic remains were found in 

 the white drift (No. 1), which, indeed, was looser in texture and 

 more calcareous, and might in consequence have been not so 

 preservative as the lower beds. Among the large blocks of 

 freestone, either impacted or strewn in a heterogeneous manner, 

 were lying seemingly entire skeletons of elephants, some of the 

 skulls and jaws furnishing good evidence of the rough usage they 

 had sustained by being broken and crushed flat by blocks which, 

 with the force of impact, had cracked the others on which they 

 impinged." He then gives some examples to show that although 

 many of the remains were thus smashed, they had evidently not 

 travelled far, as was indicated by the perfect state of preservation 



