Some Notes on the Eggs of the Sudan Crowned Crane. 69


SOME NOTES ON THE EGGS OF

THE SUDAN CROWNED CRANE.


Balearica pavonina ceciliae.


By Michael J. Nicoll.


In the Autumn of 1910 a pair of Sudan Crowned Cranes

made a nest in the Giza Zoological Gardens in which two eggs were

deposited.


As the birds seemed anxious to incubate, the eggs were not

critically examined and measured although both Captain Flower and

Mr. A. L. Butler noticed that they were strikingly different from the

eggs of both the Grey and Demoiselle Cranes. At about the time

when these eggs should have hatched both of them disappeared

being probably taken by crows or rats. This year, however, a pair

of Crowned Cranes have again nested and one egg was laid in the

nest on 22 September and the next day another was found some

little distance away in the long grass. As the birds showed no

inclination to sit I put both eggs into an incubator. They proved

to be unfertile.


As the eggs of Balearica pavonina ceciliae have so far as we

can ascertain never been described I take the opportunity of publish-

ish these notes. The most remarkable feature about these eggs is

that instead of being blotched with reddish-brown as are the eggs

of the Grey Crane Grus grus and the Demoiselle Crane G. virgo

they are white very faintly washed with greenish-blue. One, the

larger, has a hard chalky coating so hard that it can only be removed

with a sharp knife. Their measurements are as follows :—


a. The egg taken from the nest


Total length .73 mm.


Total breadth .53 ,,


b. The egg found aioay from the nest


Total length .75 mm.


Total breadth .55 ,,


The great difference between the colour of the eggs of this

Crowned Crane and those of the Grey Crane is most interesting,

though it should be remembered that while the former is a resident

in the Sudan the latter is a migrant and that both the general

appearance and the habits of the two species are widely different.



