( 426 ) 



No. 017. J ad. (winter pluraa,a;e), S. I.sabel, 3. .x. 1907. " Iris dark brown, 

 feet greyish green, bill black."' — Wing l:i(3; tail 00 ; bill 29 mm. 



[401. Plotus anhinga Linn. 



,.-<t. 



Borba (Natterer).] 



Phliis An!ihii/tt Linnaeus, Si/sl. XkI. xii. 1. p. '^18(1701;.— ex Marcgrave : Eastern Brazil) : Pelzeln, 

 I.e. p. ,32r> (Borba). 



[4(i-j. Palamedea cornuta Linn. 



Palamedea cornuli Linnaeus, .S7s^ .V<i(. xii. 1. p. 'i.S'i (nGl'i. — ex Marcgrave & Brisson : Eastern 

 Brazil and Guiana) ; Pelzeln, I.e. p. 313 (Bixnaneira). 



Cachoeira do Bananeira (Natterer).] 



[463. Alopochen jubata (Spix). 



Amerjiihntiix Spix, Ai\ Bias. ii. p. 8+. pi. cviii. (182.5.^'' ad ripara fl. Solimoens"). 

 Chenalnprx juhatiix Pelzeln, /.<■. p. 319 (^Barra do Rio Guapon'). 



Rio Madeira : Barra do R. Gnapore (Natterer).] 



III. SUMMARY. 



In the foregoing account I have only dealt with the species that have actually 

 been taken in the Madeira district, yet their nnmber conlil easily be increased by 

 adding those which were observed or collected by Natterer farther south, on the 

 banks of the Rio Guapore, as well as on the Rio Negro in the north, and which are 

 very likely to occur also in the intervening country. The Rio Madeira fanaistically 

 belongs to the great Amazonian subregioii. According to its geographical situation 

 the avifauna shows a mi.xed character, being composed partly of Ujiper Amazonian 

 forms, partly of species peculiar to the Lower Amazons, though there are, at the 

 same time, a good many characteristic species not known to occur elsewhere. For 

 many Upper Amazonian forms the Madeira Valley appears to constitute the easterly 

 limit of their range. Quite a number of them reach the left bank of the river, 

 while they are not found at all or represented by allied forms on the right side. 

 Others are met with on both banks, but not recorded from any locality farther east. 

 A certain difference apjiarently exists between the bird-life of Borba and that we 

 find farther up in the Machados district. Many striking Lower Amazonian species 

 extend along the south shore of the Amazons to Borba and even to the Rio 

 Guapore, occurring only on the right side, whose avifauna shows a decided 

 similarity to that of the Tapaj6z. Unfortunately, our knowledge of the ornithology 

 of Western Mattogrosso is far from complete, resting exclusively upon Natterer's 

 researches ; still from the scanty information as yet available it would appear that 

 the fauna of the Rio GnaporS is essentially Amazonian, while a very different lot 

 of birds was met with by the great Austrian naturalist at Villa Maria and other 

 places on the Upper Paraguay. 



The subjoined talmhir lists may serve to illustrate the above conclusions. 



(A) Species peculiar to the Madeira Valley. Unless otherwise stated they are 

 restricted to the right bank of the stream. 



