86 The Oohgists' Record, December 1, 1923. 



THE EGG OF MANTELL'S APTERYX 



{Apleryx mantelli). 



By Graham Rfnshaw, M.D., F.R.S.E., Editor of " Natureland." 



The melancholy interest attaching to the flightless birds of 

 New Zealand — now so fast disappearing under the attacks of 

 introduced stoats — renders accurate description' of their eggs highly 

 desirable, and when one happens to possess a specimen that is no 

 faded museum relic but a recent and fresh example, the duty of 

 recording it becomes almost imperative. 



It is, perhaps, the enormous size of the egg as compared with 

 the parent, that makes the Apteryx so sluggish when on the eve of 

 laying ; the bird observed by the writer was certainly very stupidly 

 tame, allowing herself to be handled, and when released merely 

 standing as if stuffed, making no attempt to run under her straw 

 coverlet, as they generally do. She had, in fact, been coming out 

 in the daytime, which under usual conditions she never did. 

 Shortly afterwards she laid an egg which weighed 11 1 oz. — not a 

 great weight for the species, the maximum recorded by Sir W. 

 BuUer reaching 15| oz. 



The specimen now before me measures five and a-quarter by 

 four inches. It is markedty — most markedly — reptilian in shape, 

 being elongated, with but little difference between the big and little 

 ends ; it also recalls the elongated, equal-ended egg of the Megapodes 

 and Brush Turkeys. The Apteryx egg, however, is very different 

 in texture from that of the Megapode, being of porcelain smoothness 

 as contrasted with the rough egg of the latter ; the shell in the 

 Apteryx is delicately thin, glossy, and dotted all over with minute 

 pits. At the large end there are a few tiny hair-like raised lines, 

 also some half-dozen minute — exceedingly minute — papilla?. 



Viewed through the blow-hole the inside of the egg is of a beauti- 

 ful pink colour, and this is faintly perceptible all over the shell, 

 even on the outside in a good light ; one may compare it to the 

 delicate tint seen in unblown eggs of the Dipper and other birds. 

 Probably it is due to the presence of the lining membrane. Be this 

 as it may, the eggs of the Apteryx are by no means of the dull 

 white, green grey, or yellowish hue described in text-books, apparently 

 carelessly recorded from faded indifferent examples. 



