Prof. E. Lonnberg on Sterna hirundo Linn. 301 



and that in this respect I have been perverse ; but even if 

 this paper serves only to lead to the establishment of exactly 

 opposite conclusions to those which I have drawn, it will 

 still appear to me to have served a useful purpose, and to 

 have directed renewed attention to a very interesting phase 

 in the history of birds. 



XV. — On Sterna hirundo Linn, and on the Name of the 

 Common Tern. By Prof. Einar Lonnberg, of Stockholm. 



[Prof. Einar Lunnberg has sent us the following contribu- 

 tion to the question as to which species of Tern Linnaeus was 

 referring when he described Sterna hirundo. Prof. Lonnberg 

 was asked for his opinion on the matter, as being a great 

 authority on the life and writings of Linnaeus and on the 

 avifauna of Sweden, by the Committee at present engaged in 

 revising the B.O.U. List of British Birds. The matter is 

 of special importance, as, if a conclusion is come to that 

 Linnaeus' Sterna hirundo is indeterminable, it would logi- 

 cally follow that the genus Sterna, which is founded on 

 that species, cannot be used either, and a new generic term 

 would have to be provided for the Terns.] 



In order to solve the question as to which bird Linnaeus 

 meant when he, in 1758, gave the name "-Sterna hirundo" 

 (' Systema Naturae/ ed. x. p. 137), it is necessary to study 

 the earlier writings of the author himself. He quotes 

 ' Fauna Svecica ' (1746) in the first rank, and it is evident 

 that "Sterna hirundo" 1758 was a common Swedish bird 

 familiar to him. 



The short diagnosis in 'Fauna Svecica ' does not settle 

 whether the Common or the Arctic Tern is intended, 

 although it is more probable that the former was in his 

 mind when he says: '^rectricibus maximis dimidiato-albis 

 nigrisque." The outer web of the lateral rectrices in the 

 Common Tern is, as a rule, much darker than that in the 

 Arctic Tern, and in the latter it is often difficult to call 

 it " niser.^^ 



