AQUATIC WA11BLER. 383 



trils a stripe of pale yellow passes backward on either 3ide 

 over the eyes and ear-coverts ; the forehead is reddish-buff 

 mixed with dark brown ; the top of the head dark brown 

 with a median stripe of pale yellow extending to the hind 

 head, and thus bisecting, as it were, the dark-coloured cap ; 

 the nape and sides of the head yellowish-buff, becoming more 

 rufous on the back, rump, and upper tail-coverts, each feather 

 of these parts having a dark median patch ; the tail brown ; 

 wing-quills dark brown with light edges, wing-coverts and 

 tertials broadly edged with pale brown ; chin and throat 

 white, passing into yellowish-buff and, uniting with the same 

 colour on the sides of the neck, forming a gorget of which 

 each feather bears a dark narrow median streak; breast, 

 belly, and lower tail-coverts pale buff ; the flanks yellowish- 

 buff with dark median stripes, forming a continuation of the 

 streaked gorget ; tail beneath dusky brown : legs, toes and 

 claws light yellowish- brown. 



The whole length is about four inches and a half : from 

 the carpal joint to the end of the third and longest primary 

 rather less than two inches and a half. 



The sexes seem to differ little in plumage, but the young 

 are said to have the throat and breast more thickly spotted 

 than the old birds. 



The species so far described here under the generic name 

 Acrocephalus agree in having short lower tail-coverts and the 

 gape beset with bristles, while the two species of which an 

 account is to follow have very long lower tail-coverts and no 

 bristles at the gape. These structural characters, combined 

 with some others that might be mentioned, point to a plausible 

 division of the genus. Further, in their general coloration 

 and their mode of nidification, the Reed-Thrush, Reed- 

 Wren and Marsh-Warbler greatly resemble each other, and 

 differ from the Sedge-bird and Aquatic Warbler. The name 

 Acrocephalus therefore might be not without some reason 

 restricted to the group containing the first three and their 

 many foreign allies, while in that case the name Calamodus 

 should be applied to the section including the last two, 

 which seem to be generically quite inseparable. 



