GLAREOLA. 



255 



the continent to the west, the ancestors of G. megapoda finding a home on the northern 

 shores of the Gulf of Guinea, and those of G. cinerea on the eastern shores of that Gulf. 



The following key is sufficient to diagnose each species when adult, but it is interest- 

 ing to know that in this genus chestnut or black axillaries appear to be always correlated 

 with black legs and the absence of a nuchal collar ; whilst white (67. cinerea) or grey axil- 

 laries (67. megapoda, 67. emini, and G. nuchalis) appear to be always correlated with pale 

 legs and the presence of a nuchal collar, which is chestnut-buff in the two former and white 

 in the two latter. 



KEY TO THE SPECIES. 



Outer rectrices more than 

 half as long again as the 

 central rectrices. 



Basal half of outer web of 

 several rectrices margined J 

 with black. 



grallaria • 



melanoptera 



pratincola 



orientalis • 



ocularis 



megapoda. 



emmi 



nuchalis 



Axillaries black . 



cinerea 

 lactea 



Axillaries black. 



y Axillaries chestnut. 



Nape with a white collar. 



Basal half of outer web of 

 secondaries white. 



With the exception of the white nuchal collar, all these characters are believed to 

 apply to young in first plumage, as well as to adults of both sexes and at all seasons. The 

 young of 67. emini and 67. nuchalis are unknown, and it is possible that, like the young of 

 G. megapoda, they have no nuchal collar. 



Of these species the second, third, fourth, and fifth have the claw of the middle toe other 

 pectinated ; the first five are large birds with wings measuring seven inches or more characters. 



