TRIBTJRA. 361 



the ninth and tenth ; the closed tail is graduated to the extent 

 of -4. 



The type specimen, the only one known, I believe, of this 

 species is now in the British Museum. It appears to me to re- 

 present an undoubtedly distinct species of Acrocephalus, which 

 may be recognized by its abnormally large bill. The bird procured 

 by Scully, and identified by him with the present species (S. F. iv, 

 p. 146), is also in the British Museum, and is without doubt a 

 specimen of Tribura major. 



Distribution. The type was obtained in the Sutlej valley not far 

 from Bdmpur. 



Genus TRIBURA, Hodgs., 1845. 



The genus Tribura contains five Indian species, of which four are 

 alpine and one an inhabitant of the plains. The former do not 

 appear to migrate beyond ascending the mountain-slopes in sum- 

 mer and descending them in winter ; but the latter is probably a 

 migrant from distant regions, spending the winter in Burma and 

 disappearing from that country in spring. 



These Warblers are birds of plain plumage, and the feathers are 

 very soft and silky in texture. Some species are spotted on the 

 breast. The sexes are alike. The spring moult is complete or 

 nearly so, and there is generally a slight difference between the 

 summer and the winter plumages. The young birds are very 

 yellow. 



The species of Tribura frequent grass and bushes, and are great 

 skulkers, and though fond of moisture they are not particularly 

 aquatic in their habits. 



The five Indian species of this genus are not perfectly congeneric, 

 one differing from the other four in its extremely large bill, whilst 

 a second species is distinguished from the other three by the shape 

 of the wing. I keep all five together, however, but subsequent 

 workers will do well to investigate their claims to generic separation. 



In T. major the bill is as long as the head ; in the other species 

 only half the length of the head ; in all cases slender and straight. 

 The rictal bristles are extremely minute and invisible without a 

 lens. The forehead is very smooth, and free from all hairs &c. 

 The wing is fairly long, the first primary varying from rather more 

 than a third to half the length of the second, which is long, but falls 

 short of the tip of the wing. The tail is very much rounded, and 

 the feathers are rather pointed. The tarsus is sufficiently long to 

 enable these birds to hop about freely. 



Key to the Species. 



a. First primary much shorter than half the 

 second 



a. Bill at gape -8 T. major, p. 362. 



b'. Bill at gape '65 T. intermedia, p. 363. 



