Birds of Celebes: Zosteropidae. 493 



These species are grouped together on the lines of Dr. Sharp e's careful 

 key to the genus, in virtue of their having yellow on the forehead and no yellow 

 stripe on the abdomen, but some species possessing both these characters are 

 undoubtedly as nearly related to some of the above species, as they are to one 

 another. 



Z. dtrinella, which we have not been able to examine, is said by Mr. Hartert 

 (5) to be the nearest ally of Z. sarasinorum: "They are very similar to each other, 

 in fact so much that they might be merely subspecies. Z. dtrinella, however, 

 is a little larger, with longer wings and beak, and has the sides of the breast 

 and abdomen more strongly washed with greyish brown, and the middle of the 

 breast and abdomen is lighter and more Avashed with pale yellow in Zosterops 

 sarasinorum" . 



The distinguishing characters of Z. palpebrosa have been pointed out, antea. 

 Z. neglecta, which from its geographical location might have been expected to 

 show close correspondence with sarasinorum is said by Seebohm to be greener 

 than the Indian bird, whereas Z. sarasinorum appears yellower when compared 

 with two specimens (though apparently not in fully adult male dress) of Zosterops 

 palpebrosa in the Dresden Museum. Still a comparison of Z. neglecta with sarasinorum 

 would by very desirable, since neglecta is also a mountain species, having come 

 from an altitude of 5000 feet in East Java (Seebohm 1. c). 



Z. anjuatiensis has the under surface more drab-tinted and the yellow of the 

 throat of a slightly duller tint (C 10229); Z.demeryi has the under surface ashy 

 grey strongly tinged with yellow (Biittik.). The differences between Zosterops 

 sarasinorum and simplex, poliogaster and ahyssinica seem from the descriptions to 

 be greater. 



The two other Celebesian Zosterops, Z. atrifrons and intermedia, are readily 

 distinguishable from sarasinorum, the first by its black forehead, the second by 

 its entirely yellow under surface; Z. anomala by its black and bare orbital ring. 



Zosterops is a genus consisting of a few well-marked types, which appear 

 to have been scattered and re-scattered by flight; and now, wherever one of these 

 types is found in a new locality, it is named as a new species. A new 

 monograph of the genus is already much needed. Dr. Hartlaub's "Versuch" is 

 now 30 years old, Dr. Sharp e furnishes a sequence of descriptions of 85 species 

 with a key, and, as already mentioned, this number has now been raised to 

 over 125. Yet it is impossible to discriminate these "species" by means of de- 

 scriptions alone; moreover next to nothing is known about the modifications of 

 their different coloiu-s with age, and these appear to be much greater than many 

 of the "species"-modifications, nor has any one, so far as we are aware, pointed 

 out between what limits of coloration and structure adult individuals from the 

 same locality are apt to vary — limits that may prove wide enough in very 

 many cases to overlap the variation-limits of the nearest ally in another quarter, 

 reducing Zosterops perhaps to some 12 — 20 clearly defined species, some of them 

 composed of a large series of ill-defined races. 



