Vol. xxxi.] 



112 



which was very pronounced, of the same colour. The eye 

 was of a curious dull white. The wings unusually pale. 



Mr. Borrer also exhibited two clutches of eggs of the 

 Common Tern (Sterna fluviatilis), of the rare red variety. 

 They were believed to be the first and second sets of the 

 same bird. They had been obtained this year in England : 

 the first set was of a most brilliant red colour, and the 

 second of a duller rust-red. 



Mr. Borrer said that these eggs were of particular interest, 

 as this type occurred, so far as he was aware, in one locality 

 only. He had received similar clutches from this colony 

 every season during the last five or six years, and they were 

 believed to have occurred there for an even longer period. 

 It was not likely that the same pair of individual birds 

 should have survived every accident of migration, and have 

 returned to the spot with unfailing regularity season after 

 season. It would appear that a strain of birds had established 

 itself in this colony, whose tendency was to lay eggs stained 

 almost exclusively with blood-pigment ; and it was possible 

 that in this manner had been evolved such erythristic types 

 as occurred in the eggs of the Blackcap in this country and of 

 the Dartford Warbler on the continent — the type developing 

 from an abnormal variety in an individual bird. 



Mr. Ogilvie-Grant exhibited and described a new sub- 

 species of Grosbeak collected by Mr. G. W. Bury in the 

 high mountains of Southern Yemen : — 



Rhynchostruthus percivali yemenknsis, subsp. n. 



Adult male. Similar to R. percivali, but with no black on 

 the forehead j the head and nape of a brighter rufous-brown ; 

 the mantle browner and the rump and upper tail-coverts 

 darker grey ; bill dark grey (nearly black) ; feet pale 

 pinkish-brown. Total length 160 mm. ; wing 92 ; tail 62 ; 

 tarsus 19. 



Adult female. Similar to the male, but smaller. Total 

 length 146 mm.; wing 89 ; tail 53 ; tarsus 18. 

 Hab. Mountains of Southern Yemen. 



