ON TIIE EXPLORATION OF THE BORNEAN CAVES. 151 



Stratum 3. — Concreted yellow clay (8 inches to 12 inches thick), with- 

 out apparent stratification, and without organic remains. This stratum 

 is sharply defined from the preceding one ; but not so from Stratum 4, of 

 which it is, in fact, an integral part. Both this stratum and the preced- 

 ing required steady blasting throughout the excavation, and any remains 

 they might have contained would have been likely to escape notice unless 

 of large size or occurring in some abundance. 



Stratum 4.— Unstratified reddish-yellow clay, with small water-worn 

 gravel, and without any kind of organic remains. This stratum rested 

 immediately on the limestone floor, which was worn into deep longitudinal 



furrows. 



The dimensions of this excavation were 23' X 6' to /', and the depth 

 varied to 6' in the deepest part. It was completed in six days, as it was 

 not necessary to follow the tedious process of washing the contents. 

 Section 1 coincides with the longer axis of the excavation, and it is in- 

 correct in one particular, i.e. it shows the black band as subjacent to the 

 deposit of clay marked 5, which is really below it. 



Excavation B. 



Stratum 1. — The black band, as in Excavation A. 



Stratum 2. — A bed of river mud, indistinctly stratified, mixed with 

 guano, and crowded with the remains of bats and of land and fresh-water 

 mollusca, together with bones and teeth of a variety of mammalia, fish, 

 and reptiles, the majority of which are much broken and waterworn. 

 Greatest depth 4 feet. This bed corresponds to the ossiferous stratum of 

 Cave V. Excavation D, with which it is essentially identical. _ The re- 

 mains, however, obtained from XIII., B, are more varied and in better 

 condition than those from Cave V. 



Stratum 3.— Unstratified yellow clay, concreted, except in its upper- 

 most part, into a hard stalagmitic rock. This deposit corresponds to the 

 strata 3 and 4 of Excavation A. It contains shells and a few bones. 

 Owing to the scarcity of these latter, and also to the influx of water by 

 underground drainage, I did not continue this trench down to the lime- 

 stone floor. 



In this excavation it was needful to wash the whole of the river-mud 

 in sieves, which caused the work to be excessively slow. During the 

 process a small V-shaped fragment of stone, seemingly artificial, was 

 found. It is that marked 110 in the Catalogue. If this fragment is 

 considered to be undoubtedly of human workmanship, it forms the first 

 evidence of the co-existence of man in the district with the fauna of the 

 river-mud horizon, and as such is not without interest. A more impor- 

 tant result of the exploration of No. XIII. is the proof obtained— meagre 

 though it is— of the presence of the remains of mammals in the yellow 

 clay lying below the river-mud deposit. 



During the quarter, I have visited fourteen additional caves m the 

 Paku and Bidi districts. One of these, known as the Guah Kokan in 

 the Kapoh hill at Bidi, is of great size, has seemingly a considerable 

 thickness of deposits, and is situated at a height of upwards of 100 feet, 

 in the face of a perpendicular cliff. It is very large for the few men at 

 my command to make an adequate impression on, but I will attempt it if 

 no better offers within the next few days. Before the completion of the 

 ensuing quarter I hope to be able to report having visited the ossiferous 



