Some months ago the question arose between us as to the principal distinguishing characters of the Fringilline and Ploceine Finches, and (naturally) this difference of number in the primaries was the first structural point to be considered. Having a wing of the common Siskin and several wings of Waxbills and Mannikins, we examined the two types, and (to our unbounded astonishment), discovered the first primary well developed in both, but with this difference:—In the Fringillid bird the first primary was shorter than, and therefore completely concealed by, its upper covert; whereas in the Ploceid bird the first primary projected beyond its covert.
Thinking it quite impossible that, if this fact were common to all examples of all species of the two families, it could have been so long overlooked, we have gradually accumulated the wings of various species in which the first primary was declared to be absent, and we are bound to say that, not only have we never failed to find it in any species which we have examined, but that in some species, such as the Sparrow (Passer domesticus) and the Canary (Serinus canaria), it is far better developed than in many of the Ploceid Finches.
We have examined wings of the following species:—
Fringillidæ.—Chrysomitris spinus, C. tristis, C. totta; Serinus icterus, S. canaria, S. leucopygius; Carduelis carduelis; Acanthis cannabina, A. rufescens; Fringilla cœlebs, F. montifringilla; Passer domesticus; Pyrrhula pyrrhula; Guiraca cærulea; Chloris chloris; Cardinalis cardinalis; Alario alario.
Motacillidæ.—Motacilla melanope; Anthus trivialis, A. pratensis.
Hirundinidæ.—Hirundo rustica.
Being anxious to make no mistake, we were not content to examine single examples, but, wherever possible, carefully removed the lower coverts from several examples of each species; in no single instance did we fail to discover the small first primary, although in Motacilla melanope it is very minute and almost linear (narrowly hastate); in fact, we found it best developed in the Sparrow, and worst developed in the Grey Wagtail. Even yet, it seemed so strange that a feather which we always discovered easily should have been so long overlooked, that we were not convinced, but determined to obtain undeve-
