414 C. J. Sundevall on the Wimjs of Birds. 



should be named after tlieir quill-feathers^ so that those 

 on the hand are called Tectrices primoi'es or manus (great 

 hand-coverts)^ and those on the forearm cubitales (great 

 arm-coverts). The former are always inserted in the skin 

 in the same tube with their corresponding quill-feathers, 

 and so close upon the latter that the two seem to have 

 grown together. The same condition occurs with those 

 of the cubitus in all birds which have large cubital feathers, 

 as already stated. 



The greater hand-coverts [T. majores primores) are equal 

 in number to the quill-feathcrs. The outer ones always 

 diminish in length more than the quill-feathers, so that the 

 first and second are shorter than the following ones, when, 

 for example, only the first quill-feather is somewhat shortened. 

 They are most frequently whole-coloured and dark, very 

 seldom spotted. 



Of the tectrices cubitales there are always one or two more 

 than of the corresponding remiges ; thus, externally, there is 

 always one small supernumerary one (/, no. 1). Properly, 

 they ought to be of equal number, as the feathers here, as 

 everywhere, are arranged in quincunx (rows of three different 

 sets), which constitutes a continuation of their arrangement 

 on the hand. The supernumerary coverts seem to me 

 therefore to show that a quill-feather, which ought to have 

 been placed in the middle of the wing-fold, is not deve- 

 loped. These coverts appear in general to increase in length 

 inwards, as the inner ones cover a greater portion of their 

 corresponding remiges than the outer ones ; but this is 

 usually due to the fact that the remiges decrease inwardly 

 somewhat in length, while the coverts do not diminish. 

 In the Song-birds they are so short that they do not attain 

 half the length of the remiges, except inwardly in some 

 genera; but in all other orders they are larger, so that they 

 always reach beyond the half of their corresponding remiges, 

 even the outermost (see figs. 7 and 10, /, of Song-birds, and 

 figs. 3 and 11, I, of another order). Only some Pici (varii) 

 and Upupa constitute an exception to this, for in this respect 

 tlicy present the same conditions as the Song-birds. 



