536 



ON THE SPECIES OF ANATID.^. 



[June 15, 



V. Neotropicai, AnATIDjE. 



The Neotropical Region is better supplied with Anatidae than any 

 other of the divisions here adopted except the Arctic, 39 species 

 being specially attributable to it. Besides these, as Mr. Salvin and 

 I have shown in our article on the Neotropical Anatidse, published 

 in the Society's 'Proceedings' for 1876*, 23 of the .\rctic Anatidse 

 are more or less regular visitants to it during the winter season. 



The generic types of Anatidae restricted to the Neotropical area 

 are 5, namely, Cairina,Heteronetta, Metopiana, Tachyeres, and Merga- 

 netta. There are, however, only 7 species belonging to these peculiar 

 genera ; so that the mass of the Neotropical Anatidse belong to 

 Arctic genera. 



On the whole, the Neotropical Anatifauna (if such an expression 

 is allowable) is not more peculiar than that of Australia, where there 

 are also 5 special generic types not found elsewhere. In true Anatidse 

 the Neotropical Region is specially rich, possessing 23 species against 

 the Arctic 18, as will be seen better by the subjoined Table. 



Table IV. Distribution o/Anatinse. 



In Fuligulinse, on the other hand, it is very poor (see Table III. 

 p. 533), having only 1 species against the Arctic 26. 



* " ReTision of the Neotropical Anatidse," P. Z. S. 1876, p. 358. 

 ^ In these genera some of the species occur in more regions than one, so 

 that the total is not equal to the sum of the constituents. 



