1884.] BIRDS'-NEST CAVES OF BORNEO. 535 



and also that it was poisonous ; to convince them it was not, I 

 allowed it to bite me. At this point I found myself at the moulh 

 of a cave named Simud Putih, i. e. the White Cave ; the entrance 

 is about 40 feet higli by 60 feet wide, and descends very steeply, 

 widening out to a great size, and having a perpendicular unexplored 

 abyss at its furthest point. This cave is used by the nest-gatherers 

 as their dwelling-place, and at the entrance are their platforms of 

 sticks, one of which was placed at my disposal by the head man : it 

 is also the cave by which the great body of the Swifts enter. Imme- 

 diately outside it is a great circular opening leading sheer down into 

 Simud Itam : this is one of the two openings mentioned as giving light 

 to that cave, and is the entrance most in use by the Bats. As sooa 

 as I had unpacked and settled down on my platform, I sallied out to 

 find the material from which the birds make their nests, as my pre- 

 vious experience is that birds do not as a rule travel far for the bulk of 

 the material they use. I was speedily successful in my search. It 

 is a fungoid growth which incrusts the rock in damp places, and 

 when fresh resembles half-melted gum tragacanth : outside it is brown 

 but inside white, and little if any change in its consistency is effected 

 by the bird ; the inside of the nest is, however, formed by threads of 

 the same substance, which are drawn out of the mouth in a similar 

 way to that of a caterpillar weaving its cocoon. 



The Malays told me to be sure and return to Simud Putih at 5 

 o'clock, as I should then see the most wonderful sight in all Borneo — 

 the departure of the Bats and the return to roost of the Swifts. I 

 accordingly took a seat on a block of limestone at the mouth of the 

 cave ; the surface of the coral of which it is composed is quite fresh 

 looking, notwithstanding that it must have been many ages in its 

 present position, several hundred feet above sea-level. Soon I heard 

 a rushing sound, and, peering over the edge of the circular opening 

 leading into Simud Itam, I saw columns of Bats wheeling round the 

 sides in regular order. Shortly after 5 o'clock, although the sun 

 had not yet set, the columns began to rise above the edge, still in a 

 circular flight : they then rose, wheeling round a high tree growing 

 on the opposite side, and every few minutes a large flight would 

 break off and, after rising high in the air, disappear in the distance ; 

 each flight contained many thousands. I counted nineteen flocks 

 go off in this way, and they continued to go off in a continual 

 stream until it was too dark for me to see them any longer. Among 

 them were three albinos, called by the Malays the Rajah, his son, and 

 wife. 



At a quarter to 6 the Swifts began to come in to Simud Putih : 

 a few had been flying in and out all day long, but now they began 

 to pour in, at first in tens and then in hundreds, until the sound of 

 their wings was like a strong gale of wind whistling through the 

 rigging of a ship. They continued flying in until after midnight, 

 as I could still see them flashing by over my head when I went to 

 sleep. As long as it remained light I found it impossible to catch 

 any with my butteifly-net ; but after dark it was only necessary to 

 wave the net in the air to secure as many as I wanted. Nevertheless 



