rx.] THEORY EXPLAINING SIZE OF THE EGG. 197 



about as large as a cheny, and it is probable that some days 

 elapse before it is ready for extrusion. As far as can be judged 

 from an inspection of the ovary, about sixteen or eighteen are laid 

 during the season. In colour they are of a pale reddish buft' 

 resembling the eggs of the black Cochin- China fowl, and their 

 flavour, though rich, is excellent. During the operation of covering 

 them with the loose black sand on which they are deposited, the 

 cock bird digs as well as the hen, and it is a most curious sight to 

 watch them at work, the sand being thrown up in perfect fountains 

 at each stroke of the powerful foot. The ]\Ialeo does not scratch 

 in the same way as the common fowl, — two strokes alternately with 

 each foot, — but, poising himself on one leg, gives several rapid digs 

 with the other, and the large foot, broad-soled and slightly webbed 

 at the base of the toes, is nearly as effective as a man's hand 

 would be. 



That the abnormal size of the egg is closely connected with the 

 nesting habits of the Maleo there can he, no doubt, but it seems to 

 me that Mr. Wallace's theory — that the instincts of the bird have 

 been made to suit its unusual ovulation — is an improbable one, and 

 that it is more reasonable to suppose that the latter is dependent 

 upon habits which have doubtless been adopted for the preservation 

 of the species. In a country such as Celebes the eggs of large 

 ground-nesting birds would be exposed to much risk. But buried 

 beneath a layer of sand, or within a mound such as is constructed 

 by Mcgapodius, they are safe from the attacks of depredators. As 

 I have already mentioned, the dej)tli at which these eggs are found 

 is often three feet or more. If the weight of a superincumbent 

 mass of gravel of this thickness be taken into consideration, it will 

 be seen that it must be such that no chick of ordinary size could 

 force its way through it to the surface, and hence it appears to me 

 far more probable that the strength and enormous size of the egg 

 are adapted to the peculiar nesting habits of the species, rather 

 than that the unusual nidification is due to an aberrant reproduc- 

 tive organisation. 



