BATS IN BURMESE CAVES. 



INTERESTING caves exist at Hpa- 

 gat, twenty-six miles up the Sal- 

 ween, from Moulmein. They are 

 hollowed out in the base of an 

 isolated limestone hill about 250 feet 

 high, rising precipitously from the river. 

 Capt. A. R. S. Anderson, the surgeon- 

 naturalist, gives an interesting account 

 of these caves in an Indian government 

 report which is abstracted by "Natural 

 Science." The entrance is about twelve 

 feet high and is much ornamented by 

 Buddhistic sculptures. As the sun was 

 setting the party took their stand on 

 the sand-spit facing the entrance of 

 the caves and soon saw a pair of fal- 

 cons leave their perch on the trees and 

 fly to and fro over the river. They 

 were speedily joined by other birds, 

 including common kites and jungle 

 crows, and the entire flock, to the 

 number of sixty or a hundred, flew to 

 the entrance of the caves, close to 

 which they remained wheeling about 

 in midair. A few minutes later the 

 bats began to issue in ones and twos, 

 and were soon pursued by the birds of 

 prey, but appeared to have no great 

 difficulty in eluding capture by their 

 rapid and jerky flight, and their pur- 

 suers made no very determined or long- 

 sustained efforts to capture them, but 

 soon returned to their vigil over the 

 cave. A minute or two passed and a 



sudden rush of wings was heard, and 

 the bats were seen to emerge from the 

 cave in a dense stream which slowly 

 became more and more packed, and 

 continued of about the same density 

 for some ten minutes and then gradu- 

 ally thinned away, until, at the end of 

 twenty minutes, the last had emerged. 

 The stream of bats when at its maxi- 

 mum was ten feet square, and so dense 

 as to closely resemble smoke pouring 

 from a chimney in a gale of wind. 

 This resemblance was increased by the 

 slightly sinuous course pursued by the 

 bats as they flew off into the afterglow. 

 They were so densely crowded that 

 they frequently upset each other and 

 fell . helplessly into the river below, 

 where they succeeded in reaching the 

 bank only to fall a prey to the expect- 

 ant crow. When the great rush oc- 

 curred the falcons, kites, and crows en- 

 tered the stream of bats and, flying 

 along with it and in it, seized as many 

 bats as they required for food. Capt. 

 Anderson, by throwing his walking- 

 stick into the stream of bats, obtained 

 six specimens. During the last twenty 

 years the bats appear to have consider- 

 ably diminished in numbers, owing to 

 the depredations of their bird enemies 

 and to their constant disturbance by 

 collectors of bat manure. 



A METAL BIRD'S NEST. 



IN THE Museum of Natural History 

 at Soleure, in Switzerland, there is 

 said to be a bird's nest made en- 

 tirely of steel. There are a num- 

 ber of clockmaking shops at Soleure, 

 and in the yards of these shops there 

 are often found lying disused or broken 

 springs of clocks. One day a clock- 

 maker noticed in a tree in his yard a 

 bird's nest of peculiar appearance. Ex- 

 amining it he found that a pair of wag- 



tails had built a nest entirely of clock 

 springs. It was more than four inches 

 across and perfectly comfortable for 

 the birds. After the feathered archi- 

 tects had reared their brood, the nest 

 was taken to the museum, where it is 

 preserved as a striking illustration of 

 the skill of birds in turning their sur- 

 roundings to advantage in building 

 their nests. 



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