324 GEOGRAPHICAL DISTRIBUTION 



(Tapaculo) — all of them low Passeres, which are absolutely pecu- 

 liai', and of Picariie, in the like condition, Galbulidx (Jacamar), 

 Moynotidse (Motmot), Rhamphastida} (Toucan), Steaforniihidx 

 (Guacharo), and Todidse (Tody) ; while still more significant are 

 the Palamedeidee (Screamer), Psophiidse (Trumpeter), certain gen- 

 eralized Limicolss as Atiagis and Thinocorys, and above all isolated 

 forms like Cariama (Seriema) and Eunjpyga (Sun-Bittern). We 

 can scarcely be wrong also in attributing to the Neotropical Region 

 the Order of Impennes (Penguin) and the singularly generalized 

 form Chionis (Sheathbill), though both have a wide distribution 

 in the South-polar seas. 



Taking the Neotropical Region to extend from Cape Horn over 

 the whole continent of South and Central America, but leaving its 

 northern frontier, if it can be defined at all, to be delimited by 

 the zoologists of the Nearctic area,^ there is hardly one that 

 exhibits more variety of physical features, and the Subregions into 

 which it may be diAdded cannot be easily traced. The six divisions 

 suggested to the present Avriter in 1875 {Encyd. Brit. ed. 9, iii. 

 p. 744) by Mr. Salvin seem to be better than the four laid down 

 by Mr. Wallace ; and, subject to some uncertain modification, as 

 just hinted, on the northern boundary, are here again adopted ; 

 but the confines of all, except one, are of the vaguest. That one 

 is the Antillean, composed of what are generally known as the 

 West -India Islands, with the omission of Trinidad and Tobago, 

 whose Fauna is distinctly continental. Beginning, however, at the 

 southern point of the Region, we seem to have a Subregion extend- 

 ing on the east coast to somewhere north of Bahia Blanca, whence 

 its boundary runs in a north-westerly direction, passing to the east 

 of Mendoza, and then northward along the eastern and higher 

 slopes of the Andes, and after trifurcating on either side of the 

 valleys of the Magdalena and its confluent the Cauca, returns along 

 the western slope of the Cordillera until it trends seaward and 

 reaches the Pacific coast about Truxillo. As the peculiarities of 

 this Subregion are mainly developed in Patagonia, the name 

 "Patagonian" has been applied to it, though its northern ex- 

 tremity is so far distant from its eponymous territory. Next we 

 have what may be called the " Brazilian " Subregion, marching 

 with the foregoing to somewhere near Potosi, whence it turns to 

 the north-east, and, avoiding the basin of the Amazons, strikes 

 the Paranahyba, thence making its way to the Atlantic. Then 

 comes the " Amazonian," consisting of the enormous basin of the 



^ As already stated, Prof. Heilprin proposes to annex to the Neotropical 

 Region a not inconsiderable portion of what has generally been referred to the 

 so-called " Nearctic Region," as, for instance, the lowlands [tierras calientes) 

 on either side of the Mexican tableland, Southern California, and some more of 

 the territoi-v of the United States of America. 



