sands and lapilli, cemented into soft rocks, very much like the rocks which I saw in the Siwalik hills. The strata have in this area a general dip S. of about 5 degrees, and are only concealed by a thin covering of vegetable soil. In these strata the Solo river had cut its channel 12 to 15 metres deep near Trinil. North and west of Trinil the Pliocene marl and limestone appear under them. When I first, in August 1891, came upon the rich bone-mine of Trinil, I had already made many finds of bones at several places round about the village. All belonged to the same homogeneous fauna which I had found in other parts of the Kendeng hills. The first fossil bones were a horn of small species of deer, which is amongst the commonest of the fauna, a molar tooth of Stegodon, and a few other remains belonging to the same fauna.
FIG. 61. Section of the Bone Strata at Trinil. (After Dubois.)
A, Vegetable soil. B, Sand-rock. C, Bed of Lapilli-rock. D, Level in which the four human remains were found. B, Conglomerate. F, Clay-rock, G. Marine breccia. H, Rainy season, level of river. I, Dry season, level of river.
They were dug out of the rock by means of chisel and hammer, and the excavations were performed in such a manner that the rock was carefully removed in thin layers. It consists (Fig. 61) from higher to lower of variously coloured sand-rock, which becomes coarser, whilst more and more lapilli occur in it, and the latter prevail in the deepest bed, about one metre thick, passing downward over into a conglomerate bed. Under this follows a bed of hardened blackish clay, sharply separated, which does not contain any bones. The latter, in the sand-rock, increase in number from higher to lower, so that the lapilli bed is the richest :— the conglomerate bed, however, contains but few bones.
"Among hundreds of other skeleton remains, in the lapilli bed on the left bank of the river, the third molar tooth was first found in September; then, the hole having been enlarged, the cranium a month later, at about one
