1901. 



ANATOMY OP GllUIf OHM BIRBS. 



633 



displaced forwards and so lying in the interspaces of the secondary 

 quills. There are several small feathers in the carpal angle of the 



Text-lig. 71. 



Wing-structure of Psophia obscura. 



Diagram of the distal secondary quills and coverts, showing the eiitaxic 

 condition. General description and lettering as in text-llgure 70. 



I. Quills on first digit. 



wing, but none of these can be identified with certainty in the 

 adult condition as carpal remex or carpal covert. The degeneration 

 of these feathers is an apocentric modification, and it is interesting 

 to find it associated with the eutaxic arrangement. 



■ BicholophidcB.—lL\\e^e&xe known to be eutaxic, and there is 

 nothing in the arrangement of the feathers to distinguish it from 

 the condition in Psopliia. In the carpal angle there is an obvious 

 carpal covert, recognized by its position. Under it is a very small 

 and degenerate representative of the remex. A plica binds these 

 two to the first large secondary quill. The degeneration of the 

 carpal remex is here, as in Psojyhia, to be associated with eutaxy, 

 but it has not proceeded so far. 



Otididcc. — In the wings of these (text-fig. 72, Otis tarda) the condi- 

 tion is markedly diastataxic. The primary coverts are distad of their 

 quills, there is a good carpal covert crossing the carpal remex, the 

 latter being bound to the first large secondary by a plica, and the 

 carpal remex with its covert being in plain sequence with the 

 secondaries and their major coverts. The transverse rows over 

 the secondary quills are plain. The diastema {x) is wide, and in 

 it Hes a major covert at the base of a normal transverse row. 



BhinocJietidce. — In these (text-fig. 73, p. 634, Rhinochetus jtibatus) 

 the wing shows the eutaxic condition. The only difference between 

 the wing of these and that of Psophia is that the carpal remex is 

 not so degenerate. It is bound to the first secondary quill by a 

 strong plica and is crossed in normal fashion by a small covert. 



Eurypygidce. — It is curious that the references in the literature 

 to the condition of the wing in Eurypyga differ. Gadow (4) and 

 Beddard (1) state that it is diastataxic; PyCraft (11)' places it in 



