INTRODUCTION. 93 



for geographic illustration is entirely new. The 

 bird-skins of Senegal, indeed, have long been made 

 an article of traffic with this and other countries, and 

 hence the descriptions of many species will be found 

 scattered in our systems. But these, comparatively, 

 are few, and there is as yet no connected account of 

 this geographic division of the African continent, 

 although it is unquestionably the richest in point of 

 splendid colouring, and inferior to none other in 

 scientific interest. 



A more general and accurate idea of the pecu- 

 liarities of this portion of African ornithology will 

 be gained, by taking a rapid glance at those of the 

 northern and southern extremities. The long line of 

 coast bordering on the shores of the Mediterranean, 

 as we have just remarked, has never been suffi- 

 ciently investigated ; but we know that those coun- 

 tries are the extreme limits of several groups, of 

 which no species are to be found on the opposite 

 shores ; while, on the other hand, very many are 

 common to both. Of these latter, the most remark- 

 able are migratory ; passing from the African conti- 

 nent to the south of Europe in the spring, and 

 returning there in the autumn. It is from among 

 these migratory tribes that Europe derives the 

 greater part of her most gaily coloured birds ; such 

 as the common bee-eater (Merops Europoeus)^\h.Q 

 golden oriole (Oriolus galbula), the European 

 roller (Coracias garrulm), the common hoopoe, 

 and several others less striking. These large flocks 

 are followed by several species of the falcon and 



