72 Zoological Society :— 
deposited. The centre is then completely covered in, and the mound 
becomes elevated to the height of several feet with the remaining 
earth or vegetable matter, assuming a conical or dome-shaped form ; 
but the large mound has the top flattened for about 3 feet in dia- 
meter. The heat that is engendered by the fermentation of the 
vegetable matter is thus retained within the mass, and causes the 
eges to arrive at the period of maturity. 
It is thought that the bird allows the centre to be but shghtly 
covered during the period of laying—for two reasons: first, that it 
may have the less to scratch away on each visit, and thus be enabled 
more easily to deposit the egg; secondly, that the eggs already laid 
may be kept ina cool and certain temperature until all are deposited; 
' while, at the same time, the rain may more readily penetrate through 
to the vegetable mass, which would hasten the rotting, and thereby 
raise the necessary heat for the hatching against it is really required. 
The mode adopted by the Megapode of Banda (Megapodius am- 
boinensis’) differs materially from that of the species above referred 
to. It is stated that the eggs of this bird “occur isolated and dis- 
persed here and there; but each egg was carefully covered by a mass 
of fragments of dry plants or leaves.” 
Another remarkable difference is exhibited in the habits of the 
small Celebian Megapode (Megapodius Gilbertii). This species is 
observed ‘‘to scratch out a hole in the rotten stump or root of a 
fallen tree, and there bury its eggs ;’’ but nothing is said about co- 
vering them with vegetable débris or other matters, which we may, 
however, suppose them to do, as is exemplified by the other species 
of this singular family. 
There are other species whose habits are still more extraordinary 
in the selection of places for the incubation of their eggs. 
One species (Megacephalon), which resides many miles away in 
the inland forests, and others (Megapodius Freycineti, M. Cumingii, 
M. nicobariensis) that live in the jungles not far removed from the 
beach, seek daily in pairs (often thus congregating in flocks of 
hundreds at the period of laying their eggs) the sea-beaches, where, 
in a retired position in the masses of sand thrown up above high- 
water mark, as well as near the neighbouring jungles, may be ob- 
served a number of holes of various diameter scratched in the sand : 
so rapidly do the birds throw up the sand, that it looks completely 
like a fountain during the operation. The holes are usually of the 
depth of 18 inches to 2 feet ; in them, itis thought that “a number 
of hens’’ deposit in succession their eggs, upright in the sand on the 
side of the same hole at a distance of a few inches between each. 
The number of eggs has been found to vary in the different holes, 
which may, insome measure, depend on the number of females that 
visit each. Each egg of the same female must, however, be, as in the 
former case, laid at an interval of some days; but whether they re- 
turn to, and lay their eggs in, a hole already formed by a single pair 
or by several pairs in company on the same day, is not quite deter- 
mined. Each separate female must, after the hole is made, when 
about to lay, scratch a place for the egg on the side within the hole, 
