110 BRITISH BIRDS. 



mandible, a few scattered worn feathers under the chin, 

 and a small white patch on the posterior part of the 

 auricular area. At this time, too, the old feathers of the 

 small white circum-orbital patch were being replaced by 

 new ones (see Fig. 4). On April 26th a small white 

 patch remained on the forehead ; the auricular area 

 was supplied by long new filamentous feathers ; only a 

 few worn and faded black feathers were to be found on the 

 top of the crown ; and the breast and back were covered 

 with a new growth of white feathers, many of those on 

 the breast having a roseate hue (Fig. 5). On May 3rd, 

 when the observations ceased, the head was entirely 

 black save for a few ragged remains of old feathers on the 



FIG. 6. — BLACK-HEADED GULL, NO. 3, ON MAY 3RD. 



forehead. At the posterior part of the black patch 

 were two or three rows of black feathers with white tips 

 (Fig. 6) (analogous probably to those found in L. atricilla). 



In No. 2 the change was exactly similar, save that the 

 new feathers did not appear till April 5th, and started 

 to grow sooner in the auricular area. This bird, however, 

 never entirely completed its moult during the summer. 



In No. 1 the changes were to all intents and purposes 

 similar. 



All my birds assumed feathers which were more of 

 a slaty black, not a brown colour, great variation in this 

 respect being seen in different individuals. 



