Family and Generic Differentiation. 339 



But, it may be asked, of wliat practical use are all these 

 facts, so far as they seem to go ? 



Well ! Here is one example of how the colour- pattern and 

 general appearance of the downy young may appear to settle 

 once and for all a debatable point in generic relationship. 



You will find in this box a nestling of a so-called Ringed 

 Plover from Australia. In any of the classical works or 

 catalogues you will always find this species included at the 

 end of the list of species presumed to belong to the genus 

 yEffia/itis. The species 1 refer to is Elseyornis melanops, 

 and, if you examine its nestling, I think you will agree with 

 me that it certainly does not belong to the genus yEgialitis, 

 but is worthy of the generic distinction which has been 

 recently bestowed upon it. 



Here is another instance, namely the downy young of 

 Oreophilus mjicollis from southern South America. Dr. 

 Bowdler Sharpe included the genus Oreophilus with the 

 Wattled Lapwings ; but if you compare this nestling species 

 of Oreophilus with the nestlings of the Wattled Lapwings in 

 this box, I think you will come to the conclusion that, 

 whatever else this interesting and aberrant form may be, it is 

 not a Wattled Lapwing. The colour-pattern is suggestively 

 Eroliine, and the natural conclusion seems to be that 

 Oreophilus is an aberrant Dunlin*. 



The Ruff {Machetes), a^hin, was placed by Bowdler Sharpe 

 with the Tringinse (Totaninse olim), but the colour-pattern 

 of the downy nestling is undoubtedly Eroliine in type, as 

 anyone may see for himself by looking at the example in 

 the front hall of the Natural History Museum at South 

 Kensington, and comparing it with the type of colour- 

 pattern characteristic of the Eroliinse. The colour-pattern 

 of the tail, tail-coverts, and rump in females and immature 

 birds is also Eroliine — this diagrammatic drawing repre- 

 senting what I mean by the colour-pattern typical of the 

 Eroliinse. Judging, too, by this last character, Micro- 

 palarna is Eroliine, while Macrorhamphus is Tringine. 



* I am free to confess that there are almost, if not quite, as good 

 reasons tn look upon it as an aberrant Dotterel {Eudromias). 



