322 CHARADRIIFORMES CHAP. 



akin to Grouse, they have since given rise to much discussion ; 

 Dr. G-adow's view here adopted being that they are highly 

 specialized forms, analogous to the Galli in their digestive 

 organs, but homologically constituting a link between the 

 Limicolae and the Columbae. 1 From the Pigeons they certainly 

 differ remarkably in the condition of the chicks, which are 

 covered with brown, creamy, and black down, and run almost 

 immediately from the shell ; yet they agree with them in most 

 points of osteology, myology, and pterylosis, while the eggs recall 

 those of Rails, and the flight resembles that of a Plover. 



The body is compact ; the bill short, arched, and fairly stout ; 

 the metatarsus abbreviated and feathered anteriorly, or entirely 

 in Syrrliaptes. In this genus, moreover, the hallux, much re- 

 duced elsewhere, is totally absent ; and the short front toes are 

 enclosed in a sort of casing, which is covered as far as the thick 

 claws with hairy plumage, the whole forming a padded foot unique 

 among Birds. The long pointed wings have sixteen or seventeen 

 secondaries, and eleven primaries, of which the outer has its 

 shaft produced into a thin filament in Syrrhaptes paradoxus ; 

 the wedge-shaped tail has sixteen rectrices, the median pair 

 being elongated and pointed in that genus and Pteroclurus (Pin- 

 tailed Sand -Grouse), if the latter be allowed to stand. The 

 furcula is U-shaped, the syrinx tracheo-bronchial, the tongue 

 lanceolate ; there is a small aftershaft, and a large crop ; while 

 the down of the adults is sparingly distributed. 



Sand -Grouse are true desert - birds, affording excellent in- 

 stances of protective coloration in their buff or brownish tints, 

 slightly varied with grey, black, orange, and white ; Pterocles 

 fasciatus and P. lichtensteini, however, prefer bushy and rocky 

 ground to bare, sandy, or stony plains. Gregarious yet mono- 

 gamous, they are shy and wary, but very pugnacious among 

 themselves ; their flight is swift, strong, and noisy ; their powers 

 of walking and running good, though rather clumsy, owing to the 

 extremely short legs. All the species lie closely until flushed, and 

 are fond of basking in the sun on their sides, in holes scraped out 

 for the purpose. Migration probably prevails to some extent 

 throughout the Family, while the irruptions of Syrrhaptes para- 

 doxus into Europe (p. 324) are quite unparalleled. The cry, 

 often uttered upon the wing, is a piercing whistle, or a twittering 



1 P.Z.S. 1882, pp. 312-332 ; Bronn's Thier-Reich, Aves, Syst. Theil, pp. 207-209. 



