28 BRITISH BIRDS, WITH THEIR NESTS AND EGGS. 



Family TURDIDsE. Subfamily TURDIN&. 



THE ROCK THRUSH. 



Monticola saxatilis, LINN. 

 A DMITTED, because one specimen was shot at Therfield, Herts., in 1843. 



So far as I can see, there is no more reason for admitting these birds to 

 our list, than for excluding the following : 



Family TURDIDsE. Subfamily TURDINsE. 



THE AMERICAN ROBIN. 



Turdus migratorius, LjNN. 



I 



OBTAINED at Dover; but excluded, on the ground that it may have 

 escaped from captivity. In these days of aviculture, even the rarest and 

 least suspected birds may have reached our shores in this manner. 



Family TURDID/E. Subfamily TURDIN^E. 



THE SIBERIAN GROUND THRUSH. 



Turdus sibiricus, PALL. 



SOME writers admit, and others exclude this species ; one example only 

 having been obtained (on the authority of a dealer) between Guildford 

 and Godalming, in the winter of 1 860-61. 



In other branches of Zoology, we should not necessarily regard a species 

 as British, on the score of one or two examples having been obtained on our 

 shores : the fact of their occurrence would be recorded, and possibly an 

 illustration published, but subsequent works would not be considered incomplete 

 which did not describe them as British. 



