of an Expedition up the Capim River. 493 



coloured ?" I asked. "It is black, white on the belly, and 

 yellow-billed, like the female." It will be easily understood 

 that I made every possible effort to excite them to bring 

 to me immediately such a male " Mutiim-pinima." They 

 brought me some, and these birds agreed altogether with 

 the oral information given about its exterior aspect. But I 

 made even a further experiment. I asked the Tembe Indians, 

 " How do you know with certainty that the birds you brought 

 arc the males of the e Mutiim-pinima ' ? " They replied, 

 " There can be no doubt, as hereabouts we have not more 

 than two sorts of Mutums: one is the red-billed ' Mutum- 

 cavallo'*", the other is the yellow-billed f Mutiim-pinima.' 

 And, as you know, these two sorts are easily recognised 

 by every child, and nobody could confound them." 



This reason and argument are really uncontrovertible. If, 

 in certain districts, yellow-billed Mutums appear always in 

 two forms — black ones with white belly and barred ones with 

 ochraceous undersides, and the former are always of the 

 male sex and the latter are always of the female sex, it is 

 manifest that the two forms belong together — that the former 

 is the male and the latter its female. This should be suf- 

 tieient, but the Indians had another even more weighty 

 proof — the direct observation of their sexual connexion ; 

 they knew thoroughly well the details of the reproduction of 

 the " Mutum-pinima." 



As will be seen, circumstances were particularly favourable 

 on the Capim River for removing this old systematic " crux " 

 about the hypothetical Crax pinima, owing to the fact that 

 there exist there only two species of Cracidee, very easy to 

 recognise — a red-billed and a yellow-billed species, the latter 

 being the " Mutiim-pinima." To this circumstance, together 

 with the especial attention I have directed since 1S!)L to the 

 solution of the problem, the success must be attributed. 

 The " Mutiim-pinima " is distributed over the interior of the 

 Atlantic side of the right-hand Amazonian shore of the 

 State of Para, namely, the upper districts of the rivers 

 Capim, Guama, and the neighbouring parts of the interior 



* This is the native name for Mitwt mitu. 



