CUESOEIUS. 



233 



Neither white axillaries 

 nor banded breast. 



C. SENEGALENSIS 



C. SOMALENSIS 



C. RUFUS 



White axillaries and 

 banded breast. 

 Ethiopian Region. 



Throughout. C. chalcopterus. 



West Africa and Nile C. .egyptius. 



Somali-Land. , „ 



fC CINCTUS. 



South and East Africa \ „ 



J [ C. BICINCTUS. 



South Africa. 



The genus Cursorius must be characterized as small and tropical. The species and Climatic dis- 

 subspecies are distributed as follows, but one of the tropical African species ranges east- 

 wards into Scinde, and several of them encroach upon temperate Africa in the south : — 



Temperate Africa 2 



Temperate species .... — 2 



Tropical Africa 8 



Tropical Asia 2 



Tropical species . . . . — 10 

 Species and subspecies of Cursorius . . — 12 



It is not surprising that even such a compact interlaced genus as Cursorius should 

 have had its share of ill-usage at the hands of the " splitters ;" but it seems to me that the 

 only natural subdivision is to regard the Coursers with white axillaries and under wing- 

 coverts and a dark band across the breast as one group, leaving the remainder to form 

 another group, each containing five species. 



The ancestors of the latter of these groups were probably resident in the Mediterranean Ancient 

 subregion during the Interglacial Period. During the cold winters of the Post-Pliocene 

 Glacial Period one party emigrated to India, and are now represented by C. coroman- 

 delicus, a second party emigrated to tropical Africa and became C. rufus and C. sene- 

 galensis, the former in the south and the latter in the west, whence, after the two species 

 became differentiated, the latter gradually extended its range until it overlapped that of the 

 former. The third party, instead of emigrating, adopted migratory habits, though not on 

 a very extensive scale, and C. somalensis is probably the result of a small migratory party 

 which overshot its mark and finally settled in Somali-Land. The three tropical species (two 

 Ethiopian and one Oriental) have probably altered least in appearance, as they have altered 

 least in climate and habits, whilst C.gallicus has altered most. 



Precisely in the same way the banded Coursers that have the most southerly range 

 have altered least, whilst the only one (C. cegyptius) which ranges almost into the Palsearctic 

 Region has altered most. 



emigrations 



2h 



