INTRODUCTION. 
93 
desert tracts ; such, as the genera Scixicola, Alauda , 
Otis, Perdix , P ter odes, &c. most of which occupy 
a much larger proportion in the ornithology of 
Southern, than they appear to do in that of Western 
Africa. The rollers and bee-eaters live entirely upon 
insects, and are only to he found in the skirts of 
thick woods ; not one of these is found in the arid 
districts of the Cape colony, while from Senegal it 
wall he seen that we now describe no less than five 
species of the latter and three of the former. 
The family of the cuckoos, again, chiefly live 
among high forest trees ; for even the European 
species is very seldom met with in districts covered 
only with low shrubs or hedges. Hence it is, that 
the birds of this group, inhabiting Southern Africa, 
are only found in the thick forests towards Algoa 
Bay, and in a few other well-wooded situations ; six 
species, however, have been received from Senegal, 
two of which belong to the splendid shining group 
of Calcytcs, met with by Le Yaillant in the forests 
just mentioned. The scansorial tribe, as every one 
knows, is strictly arboreal ; and of these we possess 
eight species. The splendid sun -birds ( Cinnyres ) 
derive their sustenance from the nectar of flowers, 
and probably from the minute insects found therein ; 
now of this single group we shall describe no less 
than eight species, some of which (from the number 
of specimens sent) must be very common. These 
facts are sufficient to show, that however arid and 
treeless may be the interior districts of Western 
Africa, yet that in Senegal there must be many 
