MILLIONS OF SMALL BATS 237
where birds'-nest soup is an expensive luxury. The natives of Borneo do not eat them. For myself, I found the soup rather tasteless.
We were told that if they missed one season's nest collecting, most of the birds would forsake these caves, possibly because there would be so little room for them to build again. I learned that they build and lay four times a year, but I think that they meant that both the black and the white-nest birds lay twice each. The white kind build their first nests about March, and the black kind in May, and, as these nests are all collected before they have time to hatch their eggs, there are no young birds till later in the year, when the nests are not disturbed, but the old nests are collected with the new ones the following year. If the guano could be easily transported to the coast it would be a paying proposition, but the Government fears that it might frighten the birds away.
About dusk that evening after we had returned to our hut, I heard a noise like the whistling of the wind, and, going outside, I saw a truly wonderful sight, in fact a sight that filled me with amazement. The millions of small bats which share these caves with the birds were issuing forth for the night from the small hole I spoke about on the very top of the rock leading into the large cave, but what a sight it was ! As far as the eye could see they stretched in one even unbroken column across the sky. They issued from the cave in a compact