OSSIFEROUS CAVES OF SICILY. 549 



ing from the milky or smoky colour of chalcedony to that of 

 jaspery hornstone. This brecciated matrix was firmly at- 

 tached to the roof, and for the most part covered over with a 

 coat of stalagmite. In the SSE. expansion of the cavern 

 near the small aperture, a considerable quantity of coprolites 

 of Hycena was fotmd similarly situated, in an ochreo-calcareous 

 matrix, adhering to the roof, mingled with some bits of car- 

 bon, but without shells or bone-splinters. In the back part 

 of the cavern, where the roof shelves towards the floor, thick 

 masses of reddish calcareous matrix were found attached to 

 the roof, and completely covered over by a crust of ochreous 

 stalagmite (fig. 6, g). It contained numerous fragments of 

 the siliceous objects mixed with bone-splinters and bits of 

 carbon. In fact, all round the cavern, wherever the stalag- 

 mitic crust on the roof was broken through, more or less of 

 the same appearances were presented. In some parts the 

 matrix closely resembled the character of the ' Ceneri impas- 

 tate ' with a larger admixture of calcareous paste. 



With regard to the fragments of the siliceous objects, the 

 great majority of them present definite forms, being long, 

 narrow, and thin; having invariably a conchoidal smooth 

 surface below, and above a longitudinal ridge, bevelled off 

 right and left, or the ridge replaced by a concave facet, in 

 the latter case presenting three facets on the upper side. 

 The author is of opinion that they closely resemble, in every 

 detail of form, obsidian knives from Mexico, and flint knives 

 from Stonehenge, Arabia, and elsewhere, and that they 

 appear to have been formed by the dislamination, as films, of 

 the long angles of prismatic blocks of stone. These frag- 

 ments occur, intimately intermixed with the bone-splinters, 

 shells, &c, in the roof-breccia, in very considerable abund- 

 ance ; other amorphous fragments of flint are comparatively 

 rare, and no pebbles or blocks occur either within or withoiit 

 the cave ; but similar reddish flint or chert is found in the 

 Hippurite-limestone near Termini. 



In regard to the theory of the various conditions observed 

 in the Maccagnone Cave, the author considers that it has 

 undergone several changes of level, and that the accumula- 

 tion of bone-breccia below and outside is referable to a period 

 when the cave was scarcely above the level of the sea. 

 Dr. Falconer pointed out the significance of the fact that, 

 although Hysena-coprolites were so abundant against the 

 roof and outside, none, or but very few, of the bones of 

 Hyaenas were observed in the interior ; he remarked also on 

 the absence of the remains of small mammalia, such as 

 Rodents. He inferred that the cave in its present form, and 

 with its present floor, had not been tenanted by these animals. 



