LI. 

 LESTRIS RICHARDSONII. (swainson ) 



Richardson's Arctic Gull. 



The Lestris Richardsonii, first characterized as a new spe- 

 cies by Mr. Swainson, and named by him in compliment to 

 Dr. Richardson, the celebrated traveller, by whom it was 

 brought home from the Arctic regions, had previously been 

 confounded with the Lestris parasiticus of Linnseus, from 

 which it is readily distinguished by its shorter tail, together 

 with many other characters. It is the common one upon our 

 coast, the true L. parasiticus being of rare occurrence; it breeds 

 on several of the Orkney and Shetland islands ; on the latter 

 upon those of Noss, Unst, and Foula, upon which I have had 

 the pleasure of seeing them in considerable numbers. Here it 

 breeds in society, as many as from fifty to sixty being met 

 with at the same place, and seems to prefer those grounds 

 which are low and marshy for the purposes of nidification, 

 laying its eggs, notwithstanding, upon some slight eminence 

 of dry ground. 



On the contrary, amongst the very numerous small islands 

 on the coast of Norway, they breed most commonly apart 

 from each other, each pair taking possession of its separate 

 island, upon the highest point of nearly all of which they are 

 constantly to be seen perched, and upon it they usually lay 

 their eggs ; sometimes, however, choosing the lower grounds ; 

 here they become the merciless persecutors of the other spe- 

 cies of sea-fowl in their neighbourhood, sucking their eggs 

 whenever they are left uncovered by their owners, and with 

 unavoidable speed of wing pursuing them over the surround- 

 ing sea, in order to compel them to disgorge those fish which 

 they have captured for themselves or for their young ones ; 

 they are the hawks amongst the feathered inhabitants of the 



