328 NATURAL HISTORY OF AFRICA. 



Cuvier), is remarkable for the changes which the male bird 

 assumes at certain seasons of the year, and which, from the 

 dropping away of the lengthened feathers of the tail, and 

 the alteration in the colours of various parts of the plumage, 

 produce a total difference in the appearance of that sex. 

 Angola is its native country. There is a nearly-allied spe- 

 cies from the Cape of Good Hope. 



The Greeks applied the name KoXotos to a small species 

 of crow, probably the jackdaw. The same term has been 

 used in later times to designate a genus of birds found in 

 Africa, though not peculiar to that continent, — the genua 

 Colius. These birds, though the structure of their feet 

 offers no analogous formation, climb trees like parakeets, 

 dwell in large troops, build together numerous nests on the 

 same bushes, and are sometimes found sleeping together in 

 masses, suspended by the feet, with their heads downwards 

 They live on fruits, and occur both at the Cape of Good 

 Hope and in Senegal. 



Of the genus Bupha^a, peculiar to Africa, there are only 

 two species, called the African and the red-billed beef, 

 eaters. The former is a singular bird, both in its aspect 

 and manners. It is frequent in Senegal, and its food con- 

 sists of the larvae of oestri or gadflies, which it picks from 

 beneath the skin of the larger cattle. Le Vaillant also ob- 

 served it in the country of the Namaquas, and he states 

 that it is usually seen in flocks of six or eight together. 



Several species of roller inhabit the African continent. 

 The European roller, commonly so called {Cor ados gar- 

 Tula), is in fact an African species, although it sometimes 

 beautifies the woods of more northern countries with its 

 azure hues. Other species are found in the Angolese and 

 Abyssinian territories. 



Of the goat-sucker tribe, genetically distributed over 

 almost every country of the world, Africa also possesses a 

 few species, of which one of great beauty was lately dis- 

 covered by Riippell, the Frankfort traveller, in Nubia and 

 Sennaar. It is the Caprimulgus eximius of M. Temminck. 



The last-named genus conducts naturally to the swallow 

 tribe, of which Africa, if not the native country, is at least 

 supposed to share with us the society for one-half the year. 

 Besides its migratory species, it possesses several of a less 

 restless character, which dwell there throughout tho entira 



