Birds of the Philippine Islands. 533 



Basilan form will probably prove to be a third representative 

 species/' 



In the British Museum collection there is only one adult 

 male specimen of 0. steerii from the island of Masbate. 

 This example differs slightly from the typical Negros bird in 

 having the stripes on the chest and belly rather narrower 

 and not quite of such a deep black colour. This difference 

 is very slight and may be merely individual. 



The folloAving key to 0. steerii and the allied Philippine 

 species will no doubt be found useful : — 



A. Under surface of inner webs of quills edged with 

 white or pale grey ; under wing-coverts and 

 axillaries grey, the former with only the faintest 

 trace of yellow towards the edges of the feathera. 



a. Tail black ; inner webs of the three outer pairs of 



feathers with a very small yellow spot at the 

 extremity, largest on the outer pair ; under tail- 

 coverts olive-yellow edged with pale yellow; 

 tertiaries grey, only the two innermost ones tinged 

 witli olive 0. assimilis. 



b. Middle tail-feathers olive, generally with a blackish 



spot near the extremity ; outer pairs black, with a 

 large yellow spot on the terminal part of the inner 

 web, the spots increasing in size towards the outer 

 pairs ; under tail-coverts bright yellow ; tertiaries 

 and outer margins of the inner secondaries mostly 

 olive O. steerii. 



B, Under surface of inner webs of quills edged with 



whitish yellow or yellow ; under wing-coverts and 

 axillaries pale grey, the former largely mixed with 

 yellow. 



c. Ear-coverts pure grey ; feathers of the throat grey, 



edged with white, producing a streaked appear- 

 ance not due to immaturity ; subterminal black 

 patch on the outer tail-feathers confmed to the 

 terminal half of the feathers. Tail i5'4 inches . . (). cinereogenys. 



d. Ear-coverts dull olive-yellow ; feathers of the throat 



uniform dark grey in adults (paler and streaked 

 with whitish in young) ; subterminal black patch 

 on the outer tail-feathers extending nearly to the 

 base of the feathers. Tail 285 to 3 inches O. basilanicus. 



C. Under surface of the inner webs of the quills edged 



with bright yellow ; under wing-coverts and axil- 

 laries uniform bright yellow O. samarensis. 



