XS.X1 



duplicate major covert o£ the remicle. to the covert of tlie 10th 

 remcx has not unfrequently been assigned the office of the 

 remicle itself. If there is really an 11th remex present, then 

 it can alvrays be identified by its imbrication^ vrhich follov, s 

 exactly the same rule as all the other flight-feathers^ by 

 having its proximal velum covert near the distal vane of the 

 proximal remex, be it ever so insignificant in size. 



Having endeavoured in the foregoing pages to demon- 

 strate the identity of a covert feather, more or less con- 

 spicuous in certain genei'a or families, but always present, 

 as -v^'ell as its relation with ]-espect to its serial value, and the 

 inferences drawn from analogies, I feel it my duty to call 

 attention to the seemingly unimportant agents which led me 

 to explain, and find out in some degree, points for which 

 no explanation has hitherto been given. Starting in an 

 inverse manner (that is to say, looking out for possible ana-, 

 logies, which I believe I have satisfactorily proved), I could 

 not conscientiously arrive at any other result than the one 

 which is laid down in the Plate, with its explanation as re- 

 gards pterylomorphism and its application. 



When we realize the degree to which Nature takes advan- 

 tage of this modification, so as to substitute quality for 

 quantity, best seen in what must be looked upon as the 

 most recent forms of the Class Aves, viz. the Passeres, then 

 we can the better imagine how that, at one time or another, 

 a type must have existed in which all the digits bore remiges, 

 with their respective coverts, though not in a manner 

 adapted for excessive aerial functions. 



From the fact of these analogies havinjr their traces still un- 

 mistakably indicated by the short major coverts, the sections 

 and groups of feathers may be traced through the plumage 

 in a more or less rectangular line, as pointed out and 

 emphasized by Mr. Goodchild, viz. in the Plovers, &c., 

 regarding the upper series of coverts. 



To such a conclusion we must necessarily arrive from the 

 ^arguments named, even had we never been acquainted with 

 such an ancient form of Archornithes as the Archcsopteryx. 



