The Pewit Gull.] OF ORKNEY. 125 



the bill and legs red ; the breast, belly, and tail white ; back 

 and wings ash-coloured. 



These are the gulls I have observed in Orkney, and I think 

 we have few more, perhaps the Winter-Mew, (Brit. Zool. 

 423), but I have never had an opportunity to examine that 

 species. — ^The * Skua and Cepphus, for ought I can hear, are 

 not to be found here. 



GENUS XXX.~-TRE TERN. 



Gen. C/jor.— Bill straight, slender, pointed ; nostrils linear ; tongue slender and 

 sharp ; wings very long ; toes, a small back toe ; tail forked. 



Species 1. — The Greater Tern. 



The Sea-Swallow, Wil. Orn. 352. Rail Syn. Av. 131. Sterna Hirundo, Lwj. 

 Sys. 227. Brit. Zool. 42Q. Brit. Zool. Illus. tab. 31. Jig. 2. Ore. Rittock. 



This bird only appears here in summer, and leaves us in 

 winter ; it comes in May, and departs when breeding-time is 

 over. 



The bill is red ; the crown of the head black ; the under- 

 side of the body white ; the back and wings approaching to 



* It is found in Shetland.— Fi'rfe the Article. 



