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BRITISH CENTRAL AFRICA 
On the lakes there are two species of Tern, one of them being a red-beaked 
scissor bill in which the upper mandible is shorter than the lower. A small 
Gull (Lancs cirrhocephalus ) is also commonly met with on all the lakes. 
A Sand grouse {Pterocles gutturalis) is found in the Lake Mweru district, but 
has not been recorded from any other part of British Central Africa. There are 
many Pigeons—none of much interest except the large woodpigeon of the high 
mountains, which is apparently a Cape species (Columba arquatrix). This bird 
is larger even than the big English stock dove. Its plumage is a greyish-purple 
with white checks, and the bill is lemon-yellow. The fruit pigeons of the genus 
Vinago are very common wherever there is any forest. In coloration they are 
extremely pleasant—grass-green, mauve, yellow, with red skin round the eyes. 
I give here a drawing of the foot of the fruit pigeon showing that it is actually 
assuming zygodactyle form, like that which obtains in so many climbing birds. 
There is more and more tendency in these pigeons for the toes to be used 
two and two in grasping the branches. No doubt the zygodactyle character has 
been assumed independently in many groups of birds and is not necessarily a 
sign of common origin. Before long we shall have a zygodactyle fruit pigeon 
which in earlier years, when naturalists depended solely on external character¬ 
istics for classification, would have greatly puzzled them as to its position. 
The Raptorial birds in this land of an abundant fauna are naturally well 
represented except in one group, the vultures. It is very strange that over the 
greater part of British Central Africa these birds should be relatively uncommon. 
According to Thomson they are exceedingly abundant on the high treeless 
plateau of Uhehe, to the north-east of Lake Nyasa. They are certainly 
abundant in numbers and varied in species in South Africa, and in East and 
North Africa. In this particular British Central Africa rather resembles the 
western forest region of the continent, in which vultures are uncommon and are 
usually limited to a species of the genus Neophron. Until recently I should 
