e 
GERYGONE KEYENSIS. 259 
This bird might pass for a young stage of G. brunnei- 
pectus (Sharpe), but when comparing it with our nume- 
rous specimens of this species, I found the bill of the new 
bird longer and much narrower, rendering the bird suffi- 
ciently distinct from its allies, even if it afterwards might 
turn out to be a young stage and that the adult might 
resemble G. brunneipectus from Aru. 
A single specimen, collected by von Rosenberg (N°. 1346 
of his original list) on Little Key Island. 
2. Gerygone aruensis. 
This species is closely allied with G. chrysogaster Gray, 
from which it is easily distinguished by its smaller bill, 
the purer ashy gray head, the much paler, more yello- 
wish (not olive-green) upper surface and its shorter wing 
and tail. Top and sides of head and hind neck pale ashy 
gray, rest of upper surface, including the broad outer ed- 
gings of quills and upper wing-coverts yellowish green 
without any tinge of olive-brown, tail-feathers brown, on 
the outer web narrowly fringed with the color of the back, 
and provided with a black subterminal bar; lores and ear- 
coverts slightly tinged with brown; chin, cheeks, throat, 
centre of chest, breast, abdomen and under tail-coverts 
white; sides of breast, flanks and under wing-coverts yel- 
low, thighs brownish gray; inner edge of quills from 
underneath whitish ash-color; bill and feet black. 
The following are the comparative measurements of the 
two allied species: 
G. chrysogaster: wing 5—5,5 cm; tail 3,8—4,3; tarsus 
1,6; culmen 1,2. 
G. aruensis: wing 4,7 em. ; tail 3,0; tarsus 1,4; culmen 1,0. 
Two males collected by von Rosenberg (Nos 662 and 
816 of his original list) on the Aru Islands. 
Leyden Museum, April 1893. 
Notes from the Leyden Museum, Vol. XV. 
