184 To the River Plate and Back 



loud noise. Nevertheless it loves soaring, and will rise in 

 an immense spiral until it wholly disappears from sight in 

 the zenith, even in the brightest weather; and considering 

 its great bulk and dark color, the height it ultimately attains 

 must be very great. On sunny windless days, especially in 

 winter and spring, they often spend hours at a time in these 

 sublime aerial exercises, slowly floating around and around 

 in vast circles and singing at intervals. How so heavy and 

 comparatively short-winged a bird can sustain itself for 

 such long periods in the thin upper air to which it rises has 

 not yet been explained. 



The voice is very powerful. When disturbed, or when 

 the nest is approached, both birds utter at intervals a loud 

 alarm-cry, resembling in sound the anger-cry of the peacock 

 but twice as loud. At other times its voice is exercised in a 

 kind of singing performance, in which male and female join 

 and which produces the effect of harmony. The male 

 begins, the female takes up her part, and then with mar- 

 velous strength and spirit they pour forth a torrent of 

 strangely-contrasted sounds some bassoon-like in their 

 depth and volume, some like drumbeats, and others long, 

 clear, and ringing. It is the loudest animal sound of the 

 pampas, and its jubilant martial character strongly affects 

 the mind in that silent melancholy wilderness. 



The Screamers, like good Christians, mate for life, 

 and though they at times congregate in great numbers, 

 it has been observed that these flocks are always 

 methodically arranged in pairs. Although the spurs 

 on their wings are formidable weapons, they are peace- 

 fully disposed, and it is only the naughty gauchos who 

 now and then teach them degenerate ways and pit 

 them against each other in the ring. 



Leaving the orange-groves behind us, we proceeded to 

 a spot where the botanist of the party insisted that he 

 must go ashore to investigate the flora of a bit of primi- 



