WAGTAILS AND ALLIED SPECIES. 



203 



much compressed, anteriorly covered with eight scutella, sharp 

 behind. The toes moderate or short, much compressed, the 

 outer slightly united at the base ; the claws generally of mo- 

 derate length, curved, and rather stout, but in Budytes long, 

 little curved, and extremely compressed. 



The plumage is soft and blended ; the feathers ovate, of loose 

 texture, with a long slender plumule. The wings are rather 

 long, broad, of eighteen quills, the first being obsolete, the next 

 three nearly equal and longest; the secondaries very long, 

 emarginate, excepting the inner three, which are tapering, and 

 of which one is so elongated as nearly or entirely to equal the 



longest primaries. The tail, of twelve narrow feathers, is always 

 long, in some double the length of the body, and more or less 

 rounded or graduated, although sometimes also emarginate. 



The skeleton is of very delicate structure, the flat bones being 

 so thin as to be transparent ; but it does not differ in any essen- 

 tial respect from that of the Alaudinae, Turdinse, and Saxico- 

 linse. 



The Motacillinas reside in open jDastures and meadows, fre- 

 quent the sides of streams and lakes, run with great celerity, 

 and have a remarkable habit of almost constantly vibrating 

 their body and especially the tail. Their flight is rapid and 

 undulatory, buoyant and graceful in the highest degree ; their 

 voice shrill, and their musical powers of a very inferior order, 

 most of them being destitute of song. 



The Budytae have feet like those of the Pipits, and their bill 

 is very similar, so that the ISIotacillinre are closely connected 

 with the Alaudinse, from which, however, they are distin- 

 guished by being of a more slender form, , by having the bill 



