126 LITTLE NICOBAR AND PULO MILO 



to proceed, to chop away the network of vegetation that over- 

 hung the water. Now and again it ran through open spaces 

 covered with tall and matted grass, and then between banks a 

 dozen feet high ; but when we were forced to stop, unable to pro- 

 ceed further, the water was still brackish, although we had almost 

 reached the hills in which it takes its source. The banks were 

 frequented by herons, redshanks and other waders, and king- 

 fishers (both P. leucocephala, with sandy head and body and 

 blue wings, and the tiny bengalensis^ the counterpart of our 

 English bird). Several beautiful butterflies were seen, a rather 

 common species, with velvety black wings, blotched with turquoise, 

 constantly flitting up and down the course of the stream. 



We obtained good water in the harbour; slightly to the 

 west of the little bay, a rocky hill makes an angle with a little 

 beach of bright sand, and at the point of junction a path leads 

 to the spring a few yards inland, where, in the jungle, the 

 trickling water runs down a face of black rock, and collects in 

 a stony basin. By forming a slight dam at the foot of the 

 rock, any quantity can be collected. 



In the rocky hill just mentioned, we discovered several caves, 

 which run inwards from mouths situated at the water's level. 

 These are the homes of thousands of tiny leaf-nosed bats 

 {Hipposideros nicobarulcB, sp. nov.), and immense numbers of the 

 bird's-nest swift {Collocalia lincJiii). 



The largest of these caves is about 50 feet deep, and 20 feet 

 high at the entrance ; but at the back the accumulation of guano 

 is so great that there is barely room to stand. As we entered 

 with a lantern, our feet sinking ankle-deep into the soft chocolate- 

 coloured floor, there was a continual rush of little bats and birds 

 overhead as they sought to escape, and with a leafy branch we 

 knocked over a number of each kind before going to the end. 



The rock at the back was covered with countless numbers of 

 the shallow cup-shaped nests of saliva-gummed moss : so closely 

 were they built, that in many cases one could not place a finger- 

 tip on the rock between them, and often they were constructed 

 one on the side of the other. Nearly every one contained two 



