366 STRUCTURE AND CLASSIFICATION OF BIRDS 



ulnar side (in Charadrius as well as Laridse) which have been 

 duly described in the foregoing pages. Nor are there any 

 salient facts, save such as are evidently associated with loss 

 of the power of flight, which contradict such a placing. 



GRUES 



Definition. Oil gland present and tufted; ' feathers with an aftershaft. 

 Rectrices, twelve. A quintocubital or quintocubital.'-' Ambiens, 

 semitendinosus, and accessory always present. Expansor secun- 

 dariorum present. Cseca large. 3 Skxill schizognathous, sehizo- 

 rhlnal, without basipterygoid processes. Two carotids. 



Among the typical cranes of the family Gruidae I include 

 not only the nearly cosmopolitan Grus and the African 

 Balearica, but also the South American Aramus. 



There are no particular remarks to be made about the 

 pterylosis, which NITZSCH states to be precisely like that of 

 PsopJiia (see below, p. 374). 



The muscular system is fairly uniform in its characters, as 

 will be seen from the length of the above definition. 



The tensores patagii of the demoiselle crane (G. virgd) 

 are furnished with a muscular biceps slip, which is reinforced 

 by a tendon springing from the biceps below the origin of the 

 biceps slip. There is also the usual fibrous junction with 

 the deltoid crest of the humerus. 



From the pectoralis 4 springs a broad flat tendinous slip, 

 which joins the undivided tensor patagii. The tensor brevis 

 divides at once into two thin broad diffuse tendons, of which 

 the anterior sends forward a wristward slip, from whose 

 junction with extensor metacarpi a slight patagial fan pro- 

 ceeds to the ]ongus tendon. 



In Grus leucogeranos the tensor brevis tendon widens out 

 shortly after crossing biceps slip into a wide diffuse band, 

 composed of many strands, but not distinctly separable into 

 two or three tendons. There is a patagial fan. 



1 Except in Mesitcs, Cariama, and Rliinoclietus. 



- Rhinochctus, Cariama, Psopliia. 3 Not in Eitri/pyga. 



4 The pectoralis I. is usually stated to be single. It appeared to me to be 

 distinctly double in Grus carunculatus and in Balearica pavon ma, especially 

 in the latter. 



