6 JOURNAL, BOMBAI NATURAL HL8T. SOCIETY, Vol. XXIV. 



shells tell their own tale, almost all the small holes in pink eggs and all 

 the largest holes in^the brownish ones. 



" I saw a considerable number of these mounds, chiefly in Galatia 

 Bay, and there I examined some of them very minutely. These were 

 situated just inside the dense jungle which commences at Spring- 

 tide high-water mark. It appeared to me that the birds first 

 collected a heap of leaves, cocoanuts, and other vegetable matter, and 

 then scraped together sand which they threw over this heap, so as not 

 only to fill up all interstices, but to cover everything with about a foot 

 of pure sand. I say sand, but this term is calculated to mislead, because 

 it does not contain much silex, but consists mainly of triturated coral 

 and sheUs. After a certain period, whether yearly or not I cannot of 

 course say, the birds scrape away the covering sand layer from about 

 the upper three-fourths of the mound, cover the whole of it over again 

 with vegetable matter, and then cover it over again with the sand. In 

 the large mound, an old one into which I carefuUy cut a narrow section 

 from centre to margin, this arrangement was very perceptible ; in it 1 

 thought I could trace by the more or less wedge-shaped portions of pure 

 sand along the base, the remnants of successive outer coverings of sand, 

 the basal portions of which have never been removed, ten or perhaps 

 eleven successive renovations of the mound ; even the central portion 

 was perfectly cool. The vegetable matter had in a great measure dis- 

 appeared, leaving only the hard woody portions behind, but showing 

 where it had been by the discolouration of the sand. The decay of the 

 vegetable matter, and the birds' habit (as I judge from appearances) of 

 not removing the basal portion of the sandy covering at each renovation, 

 sufficiently explain why the mounds increase so much more in radius 

 than in height. 



''A smaller mound, as I take it still in use, though I could find no eggs 

 ■ in it, contained a much greater amount of vegetable matter, and was 

 sensibly warm inside. I could make no section of it, as it was too full 

 of imperfectly decayed vegetation. I believe that the bird depends for 

 the hatching of its eggs solely on the warmth generated by chemical 

 action. The succulent decaying vegetation, constant moisture, and 

 finely triturated lime, all combined in a huge heap, will account for a 

 considerable degree of artificial heat. 



" I am by no means satisfied that only one pair of birds use the same 

 mound. On the contrary, the Nicobarese I had with me that day, 

 explained, as I understood, that the one pair begin the mound, they 

 and all their progeny keep on using and adding to it for years, 

 and as 'Cuxemj' or whatever the wretch's sobriquet was, interpreted, 

 the men with us had during the previous month, taken at one time some 

 20 eggs out of one and the same mound, which also they took us to see, 

 and which was perhaps 6' high and 16' or 18' in diameter, and which was 

 the freshest looking 1 had seen. 



" The eggs are excessively elongated ovals, enormously large for the 

 size of the bird. They vary a great deal in size, and a good deal in 

 shape ; all are much elongated, but some are more like turtle's eggs 

 than those of a bird. When first laid they are of a uniform ruddy pink 

 as we know from having obtained one before the bird had even time to 

 bury it ; after being buried, so long as the egg remains quite fresh, it 

 continues a pale pink, but as the chicken develops within, the egg 

 becomes a buffy stone colour, and when near about hatching it is a very 

 pale yellowish brown. The whole colouring matter is contained in an 

 excessively thin chalky flake, which is easily scraped off, having a pure 

 white chalky shell below ; this outer coloured coat seems to have a 



