Mr. D. G. Elliot on the Trochilidte. 



157 



It is thus seen that with a tolerably large series of speci- 

 mens a gradual increase of length of bill is obtainable^ from 

 the shortest up to the very longest ; and I have no doubt that 

 additional specimens would give an uninterrupted scale, and 

 complete the gradations in the list here published. In no in- 

 stance, however, do the wings and tail together of any two spe- 

 cimens exactly agree in their measurements, although occasi- 

 onally one or other is found to measure the same as that of 

 some other specimen. It would seem therefore to be pretty 

 satisfactorily established that size in these birds, by itself, is 

 of no specific value whatever, and that the various specimens 

 described as distinct, chiefly upon their difierence of mea- 

 surements, must become synonyms of the C. angustipennis 

 of Fraser. 



If it could be shown, however, that all the specimens from 

 any one locality presented a diflierence in size, either gi-eater 

 or less, as the case might be, but nevertheless constant, it 

 might then perhaps be necessary to consider whether they 

 should be deemed geographical races ; but what are the results 

 shown by the table ? The bird with the smallest bill comes 

 from Panama, viz. •60 inch ; but a specimen, also from Pa- 

 nama — in fact, several have bills -70 (•lO of an inch longer). 



