﻿106 ON THE CLASSIFICATION OF BIRDS. 



the flat direction in which this member is carried by 

 ordinary birds. A compressed tail, however, is even 

 more concave than the latter are convex : the lateral 

 feathers, instead of being directed upwards, diverge 

 downwards, while those of the centre are the most ele- 

 vated. But not to perplex the reader with a more 

 technical definition, he has only to look to the tail of a 

 domestic fowl to gain a clear knowledge, at least of the 

 appearance, of the structure we should fully describe 

 but for so familiar an example. There are few in- 

 stances, however, out of the genus Gallus, where this 

 particular structure is met with. Among the perching 

 birds, we only know of the two species composing the 

 genus Alecturus, and certain males of the Widau 

 finches ; but these latter lose their singular- shaped 

 tail feathers after the breeding season. 



(100.) 13. Fasciculated, or plumed tails, are still more 

 rare than any of those we have now enumerated : the 

 feathers do not, to all appearance, lay in any regular or 

 determinate order, but rather give the idea of being 

 fasciculated, or formed into a bunch. Such is the tail 

 of the ostrich ; while the plume-tailed honeysucker of 

 Southern Africa seems to have the feathers equally 

 irregular, but upon closer examination this is not found 

 to be the case : they are inserted in the ordinary 

 manner, but the central feathers are so long, and so 

 flexible, that, instead of retaining their right position in 

 the series, they fall over each other, and thus assume 

 the appearance of being fasciculated at their base. 



(101.) 14. A scansorial tail is perhaps of more es- 

 sential importance to the birds which possess it, than 

 any other modification of this member is to other birds ; 

 at least, it will appear so because we know more of its 

 particular functions than of any other. Its form, as be- 

 fore remarked, is generally cuneated, but it is sometimes 

 rounded, and in a few birds we have instances of a 

 scansorial tail being quite even. Its distinguishing- 

 peculiarity, however, rests on the structure of the shaft, 

 which is at all times remarkably stiff, and in some in- 



