XANTHOCHROISM—VELLOW 1055 
xX 
XANTHOCHROISM, the abnormal replacement of another 
colour, generally green, by yellow, not unfrequently seen in 
Parrots ; but said to be often induced artificially (¢f CoLour, 
page 99). 
XENICUS, the generic name! of a little bird from New Zealand, 
long known as the Long-legged Warbler (Latham, Synops. ii. p. 465) 
or Motacilla longipes of Gmelin, and exciting little curiosity until 
A. W. Forbes shewed (Proc. Zool. Soc. 1882, pp. 569-571) that it, 
as well as Acanthidositta*—the RirLEMAN of the colonists (supré 
ACANTHIDOSITTA. XENICUS. 
(From Buller.) 
p. 789, note), to which genus it had sometimes been referred—had 
not the characteristic vocal organs of the OSCINES, and belonged to 
the group which Garrod termed Mrsomyopr. X. longipes is the 
Bush-Wren of the colonists, while a second species, their Rock-Wren, 
X. gilviventris, inhabits the Southern Alps. The existence of these 
two, morphologically-low genera, forming a Family which should 
rightly be called Acanthidosittide is a very significant feature in 
New-Zealand ornithology (cf. Buller, B. NV. Zeal. ed. 2, pp. 108-115). 
bs 
YAFFIL, YAFFINGALE, variously spelt, names of the Green 
WOODPECKER (page 1046). 
YARWHELP, an old name for the Black-tailed Gopwit when 
it inhabited this country (¢/. WHAUP). 
YELLOW, used in combination in the name of many kinds ; 
1 Said by G. R. Gray (Cat. Gen. B. p. 31) in 1855 to have been bestowed by 
him in 1853 ; but no publication at that date is known, and the genus was not 
really described till some years later (bis, 1862, p. 218). 
? Originally miswritten by Lafresnaye (Mag. de Zool. 1842, Ois. pl. 27) 
Acanthisitta, 
