118 GENERAL ORNITHOLOGY. 



in form and function. The whole of the existing Ratitce have rudimentary or very imperfect 

 wings, as was the case with the Cretaceous Hesperornis ; but the contemporary of the latter, 

 Icthyornis, and the still more ancient ArchceojJteri/x, appear both to have had excellent ones. 



The disposition of the remiges in their mutual relations is very noteworthy. They have 

 a rigid hollow barrel of great resistant powers, considering the amount of substance, — just 

 like the cylindrical stern of the cereal plant; a stout, solid, highly elastic shaft; the outer web 

 narrower than the inner, with its barbs set at a more acute angle upon the shaft. Any one 

 of these stiifer outer vanes overlies the broader and more yielding inner vane of the next outer 

 feather, which, on receiving the impact of air from below, resists as it were with the strength of 

 a second shaft superimposed. Though the "way of an eagle in the air" was a mystery to the 

 wise man of old, the mechanics of ordinary flight are now better understood. But the sailing 

 of some birds for an indefinite length of time, up as well as down, without visible motion of 

 the wings, and without reference to the wind, remains an enigma. The flight of the albatross 

 and turkey vulture, I venture to afiirm, is not yet explained. The riddle of The Wing will be 

 read when we know how the archsaurian escaped from ilus to aether. 



The number of true remiges ranges from about sixteen, as in a humming-bird, to up- 

 wards of fifty, as in the albatross. Their shape is quite uniform, minor details aside. They 

 are the stiflfest, strongest, most perfectly pennaceous of feathers, without evident hyporhachis, 

 if any. They are generally lanceolate, that is, tapering regularly and gradually to an obtuse 

 point, though not infrequently more parallel- sided, especially those of the secondary and 

 tertiary series. Either or both webs may be incised toward the end ; that is, more or less 

 abruptly narrowed ; this is called emargination (see fig. 343); their ends may be transversely 

 or obliquely truncate, or nicked in various ways. In a few birds, apparently for purposes of 

 sexual ornamentation, they are developed in bizarre shapes of beauty, with evident decrease of 

 utility as flight-feathers. Those of the ostrich and penguin tribes share the peculiarities of the 

 general plumage of these extraordinary birds. Remiges are divided into three classes or series, 

 according to where they grow upon the limb, whether upon the hand, the fore-arm, or the 

 upper arm. In this distinction is involved one of the most important considerations of practical 

 ornithology, of which the student must make himself master. The three classes of quill- 

 feathers are: 1. the pr//HrrriVs; 2. the secondaries ; 3. the tertiaries. 



The Primaries (Fig. 30, b) are those remiges which grow upon the pinion, or hand- 

 and finger-bones collectively (fig. 27, CtoD). Whatever the total number of the remiges 

 may be, in nearly all birds tvith true remiges the Primaries are either nine or ten in number. 

 The humming-bird with sixteen remiges, the albatross with fifty or more, each have ten 

 primaries. The grebes and a few other birds are said to have eleven primaries : if this be so, 

 it is at any rate highly exceptional. No instance of a higher number than this is known 

 to me. Again, it is only among the highest Passeres that the number nine is found, the 

 Oscines having indifferently nine or ten. In a good many Oscines, rated as nine-primaried, 

 there are actually ten, though the outermost is so rudimentary, and even out of alignment 

 with the developed primaries, that it is not counted as one of them. Among Oscines, just this 

 difference of one evident and unquestionable primary more or less forms one of the best distinc- 

 tions between the families of that suborder. So the tenth feather in a bird's wing, counting 

 from the outside, becomes a crucial test in many cases ; for, if it be last primary, the bird is 

 one thing ; if it be first secondary, the bird is another. In such cases the necessity, therefore, 

 of determining exactly which it is becomes evident. Of course it is always possible to settle 

 the question by striking at the roots of the remiges and seeing how many are seated on the 

 pinion; but this generally involves some defacing of the specimen, and there is usually an 

 easier way of determining. Hold the wing half-spread : then, in most Oscines, the primaries 

 come sloping down on one side, and the secondaries similarly on the other, to form where they 



