26 TRANSACTIONS OF THE PLYMOUTH INSTITUTION. 
animal matter at 30*58, in a sheep at 26*54; and in a human 
forearm at 31*11. We find the whole question of the proportion 
of animal matter in fossil bones summed up in Ure as follows : 
"The quantity of organic matter in fossil bones varies considerably; 
in some cases it is found in as large a quantity as in fresh bones, 
while in others it is altogether wanting. Carbonate of lime generally 
occurs in far larger quantity in fossil than in recent bones. " 
With these observations I give an analysis of a deer bone from 
the Cattedown breccia, very kindly made for me by Mr. Henry S. 
Billing, f.i.c, f.c.s. 
FOSSIL VERTEBRA OF DEER. „ . 
Ash . . . ... 89*06 
Organic matter , . . . . 10*94 
Insoluble matter . . . 2*56 
Phosphate of lime . . .. 69*43 
Phosphate of magnesia . . *71 
Carbonate of lime . . .. 11*36 
Of human handiwork there is but one certain illustration ; 
though it is quite possible, as already hinted, that some splinters 
of horn found in the breccia may be artificial. On them, however, 
I lay no stress. The certain example is a nodule of flint, already 
referred to as being the only piece of foreign stone found in the 
course of the excavations. This nodule is white and porcellaneous 
in general aspect — a natural flint pebble, about a third of the 
mass of which has been broken off longitudinally, and a portion 
of one end slantwise. Flakes have been struck from it, and it 
also suggests a probable use as a hammer-stone, at all events in a 
casual way. There is no ground for doubt that the flaking is 
artificial ; and I am glad to have the high authority of Mr. A. W. 
Franks, f.r.s., f.s.a., of the British Museum and Christy Collection, 
in support of that view. The extreme length of the nodule is 
4 J- inches, its extreme breadth 2f, and its depth inches. 
Originally it must have approached 6 inches in length, and 
4 in depth, and have been of a flattened ovoid or discoid shape. 
It is partially encrusted with stalagmite. Its present appearance 
is shown in the annexed sketch by the finder, my son, which gives 
both the broken faces, and indicates the flaking on the larger. 
The fauna of the cave comprises at least thirty-three species, 
including man, rhinoceros, lion, hyaena, wolf, fox, dog, badger, 
weasel, polecat, bison, urus, long-fronted ox, red-deer, roe-deer, 
