364 Capt. G. E. Shelley on Birds 



" The sketch of the trachea belonging to a male of Stido- 

 netta ncevosa, which is appended [p. 363], shows that the bony 

 labyrinth, which is asymmetrical in the Common Domestic 

 Drake, is replaced by a slight swelling of the inferior larynx 

 only in the present species, and that the trachea is, moreover, 

 symmetrical. 



" So far there is no difference as regards the two sexes. 

 Where the male bird of Stictonetta navosa differs from the 

 female is in the two expansions occurring at irregular 

 distances in the course of the trachea. The upper one is 

 about equidistant from the pharynx proper and the second, 

 while the lower one is placed somewhat higher from the 

 inferior larynx than the first one is from the pharynx. These 

 swellings, when the trachea is in situ, are ^compressed,' and 

 accordingly, when viewed from the front, are not conspicuous. 

 Viewed in the profile, however, these contours are plainly 

 visible, as is shown in the sketches. 



''The trachea of the female bird is more or less cylindrical 

 throughout its entire length.^' 



XXXI. — On a Collection of Birds from the Tanganyika 

 Plateau, in British Central Africa. By Capt. G. E. 

 Shelley, F.Z.S. 



(Plates V. & VI.) 



As I am kindly informed by Lt.-Col. W, H. Manning, 

 H.B.M. Deputy Commissioner for British Central Africa, 

 the present collection of birds was made during the months 

 of July, August, and September last year by the hunters 

 belonging to the Scientific Statf at Zomba, who were tempo- 

 rarily attached to the Commission for the Delimitation of 

 the Anglo-German Boundary between Lakes Nyasa and 

 Tanganyika. The Commission landed in July at Karonga, 

 about 10° S. lat., and during its stay there some specimens 

 were collected at Mpata, ten miles to the westward. The 

 expedition then travelled due north to Fort Hill, on the 

 Song we River, which forms a portion of the Anglo- German 

 boundary, and followed the Stevenson Road through the 



