THE CAROLINA BAT 173 



cave, and is the entrance most in use by the bats. As 

 soon as I had unpacked and settle-.! down on my platform 

 I sallied out to find the material from which the birds 

 make their nests, as my previous 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 traga- 

 canth ; 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 five o'clock, as I should then see the most won- 

 derful 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 Iime3tone 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 

 Sirnud Itam, I saw columns of bats wheeling round the 

 sides in regular order. Shortly after five 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, wheel- 

 ing 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 nine- 

 teen 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 six the swifts began to come into 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 



