374 CLASS xvi. 



Orus, Ardea, Numenius, Anas, Larus, Sterna, and some others. 

 To the old world are proper: Vultur (in the strict sense), many 

 sub-genera of the genus Sylvia (Sylvia, Luscinia, &c.), Oriolus, 

 Alauda, except a few species forming the sub-genus Otochoris, 

 Yunx, Buceros, Phasianus. Of these genera some are common to 

 Asia, Europe and Africa; to Asia especially are proper Pavo and 

 Casuarius, to New Guinea Paradisea; African genera are Muso- 

 phaga, Numida and Buphaga. Proper to New Holland are the 

 genera Scythrops, Strepera, Menura. As tropical forms, which 

 have species in both hemispheres, we notice especially in America 

 and Asia the numerous genus Psittacus, of which, however, some 

 species are met with in the southern hemisphere and in America at 

 higher latitudes ; also Parra, and amongst the swimming-birds, 

 Phaeton, Rhynchops and Plotus. Proper to the western hemisphere 

 are the genera: Cathartes (Sarcorhamphus) , which represents there 

 the genus Vultur of the old world, Anabates, Dendrocolaptes, Ty- 

 rannus, Pipra, Icterus (and Cassicus), Tanagra (which here repre- 

 sents the genus Fringilla, almost proper to the old world, and in 

 Africa so numerous in species), Rhamphastos, Grotophaga, Penelope, 

 Crax, Meleagris, Tinamus, Psophia and others ; also, what we here 

 name the last, but which perhaps from its numerous sparkling and 

 ornamented, though small species, is not the least remarkable, the 

 genus of the Humming Birds ( Trochilus) *. 



With the geographic distribution the migration of birds is 

 closely connected; this is the name given to the journeys under- 

 taken by many of them at stated times of the year, in order to pass 

 the winter in warmer regions, often far remote from the countries 

 where they make their nest 2 . There are only few birds in the 

 temperate and cold climates which pass the whole year in the 



1 Compare on this subject TREVIRANUS Biologic, n. s. 171 263, TIEDEMANN 

 Zoologie, in. s. 333 468, ILLIGER Tabellarische Uebersicht dcr Verbreitung der Vogel, 

 Abhandl. der Akad. der Wiss. zu Berlin, 1812, 1813, s. 221 u. ff., WILBRAND und 

 RITGEN Gemdlde der organ. Natur, Giessen, 1821, 8vo, ss. 89 in. 



3 See respecting it, amongst others, E. D. ECKMARCK Migrationes Avium in LINN. 

 Amosn. Acad. iv. pp. 565 600 (extracts from CATESBY, HASSELQUIST and KLEIN), 

 H. SCHLEGEL Verhandeling over het trelcken der Vdgels, NatuurTc. Verhand. van de 

 Hott. Maatsch. der Wetensch. 1823, xvi. 2, 1. 1. 129 292. Also the articles compiled 

 from many writers, by SMELLIE Philosophy of Nat. Hist. Edinb. and London, 1 790, I. 

 PP- 473 49 2 ; b y VIREY Now. Diet, d'ffist. nat. xx. 1818, pp. 534547, and espe- 

 cially by TIEDEMANN Zoologie, in. s. 580 642, may be referred to. 



