566 PATAGONIAN EXPEDITIONS: ZOOLOGY. 



Mr. Darwin has so unfortunately said: 'It is a Woodpecker which never 

 climbs a tree' (Origin of Species, p. 165). I will reserve for another letter 

 an account of this interesting bird. Between the strips of high ground I 

 have mentioned and the river itself is a low swampy region, often flooded, 

 and covered with sayus-trecs, interspersed with beds of aquatic shrubs, 

 canes, and reeds. Though there is here in summer a tropical profusion 

 of splendid flowers, the sombre foliage of the trees, and sere withering 

 color of the reeds, give it a peculiarly sad and desolate appearance. This 

 say//s-sw2Lmp is a great breeding place for the Carranchos [Polybori) and 

 other Hawks, of which there are great numbers of all the species known 

 in this country. But in this region I have met with a very few species 

 of the small birds found on the pampas. This part of its fauna, like its 

 vegetation, being derived from the north, differs from that of the adjacent 

 country. All such species as are found exclusively in the riverine forest 

 which I have described may be considered as reaching the extreme southern 

 limit of their geographical range at about one degree south of the city of 

 Buenos Ayres. I will now tell you what I have learned of some of these, 

 and will mention others in future." 



Genus IBYCTER Vieill. 



Type. 



Ibycter, Vieill. Analyse, p. 22 (1816) ; Sharpe, Cat. Bds. 

 Brit. Mus. i. p. 34 (1874); Sharpe, Hand-list Bds. 



i. p. 244 (pt.) (1899) /. amevicanus. 



Daptrms, Vieill. Analyse, p. 22 (1816) /. ater. 



Gymnops, Spix. Av. Bras. i. p. 11 (1824) /. ater. 



PhalcobcEims, Lafr. in D'Orb. Diet. iii. p. 151 (1843) • I- megalopterus. 

 Senex, J. E. Gray in Jard. & Selby, 111. Orn. n. S. pi. 



n 24 (1893) /• attstmlis. 



'^' ^triorchis, Kaup, Classif Saug. u. Vog. p. 124 (1844). /. aitstralis. 



Helotriorchis, Reich. Av. Syst. Nat. pi. xcviii (1850) . /. ausfralis. 



Geographical Range. — From Guatemala and Honduras southward, 

 throughout all South America to the Straits of Magellan, Tierra del 

 Fuego, Cape Horn and the Falkland Islands. 



Ibycter megalopterus (Meyen). 

 Aquila megaloptera, Meyen, Beitr. p. 64, pi. 7 (1834). 



