MANAKIN 533 
wing-bones of these birds are also much thickened, no doubt in cor- 
relation with this abnormal structure. A like deviation from the 
ordinary character is found in the allied genus Manacus or Chiro- 
machexris, comprehending 7 species, and that gentleman believes it 
enables them to make the singular noise for which they have for 
long been noted (cf. Sona), described by Mr. Salvin (Jbis, 1860, 
p. 37) in the case of one of them, J/. candxi, as beginning “with a 
sharp note not unlike the crack of a whip,” which is “ followed by a 
rattling sound not unlike the call of a landrail” ; and it is a similar 
habit that has obtained for another species, J/, edwardsi, the name 
Firru, Srxtu, anp SEVENTH SECONDARIES CoRRESPONDING FEATHERS OF THE FEMALE, 
OF THE MALE MACHROPTERUS DELICIO- SHEWING THE SAME ASPECT, 
SUS; THE FIRST TWO FROM ABOVE, THE 
LAST FROM BENEATH. 
(From the Proceedings of the Zoological Society, 1860, p. 90.) 
in Cayenne, according to Buffon (Hist. Nat. Oiseaux, iv. p. 413), of 
Cassenoisette. 'This view is supported by Mr. Layard, who, writing of 
the last species, says (Jdis, 1873, p. 384)—“ They make a curious 
rattling noise (I suspect, by some movement of the oddly shaped 
wing-feathers), which constantly betrays their presence in the 
forests,” while of the congenerie JZ. gutturosus, Mr. J. F. Hamilton 
remarks (/tis, 1871, p. 305)—“The first intimation given of the 
presence of one of these birds is a sharp whirring sound very lke 
that of a child’s small wooden rattle, followed by two or three sharp 
snaps.” The same observer adds (loc. cif.) of a member of the 
kindred genus Chiroviphia, containing 5 species, that C. caudata is 
known to the Brazilians as the Fandango-bird from its “habit of 
performing a dance.” ‘They say that “one perches upon a branch 
and the others arrange themselves in a circle round it, dancing up 
and down on their perches to the music sung [?] by the centre one.” 
Exception must be taken to this story so far as regards the mode in 
which the “ music ” is produced, for these birds have no true song- 
