72 Proceedings of the Royal Physical Society. 



interference. But this would lead us into a field which 

 properly lies outside of the work of our Society. I merely 

 hint at the existence of this field. It is one of immense 

 interest to the philosophic naturalist. Leaving such topics, 

 however, I conclude from the foregoing notes : 



1. That the supply of bird- supporting berries was much 

 below the average last autumn. 



2. That the number of our winter birds of passage has been 

 smaller this season than usual. 



3. That the present winter has been one of very excep- 

 tional mortality among birds. 



4. That the forms which have suffered most are those (1.) 

 which depend on berries, and those (2.) which depend on 

 worms and slugs — the mixed feeders having an advantage. 



5. That certain species are enabled to some extent to 

 neutralise the exceptional severity of the weather by having 

 recourse to partial migrations. 



VII. Note on the Migration of the Pied Wagtail (Motacilla 

 Yarrellii). By A. B. Herbekt, Esq. 



(Read ]5th January 1879.) 



Walking along Inverleith Eow one evening, just before 

 sunset, in the middle of last September, I heard repeatedly 

 the well-known call-note of the pied wagtail, and, looking up, 

 saw on two of the houses a large assemblage of these birds, 

 sixty or seventy at the least ; and there may have been 

 double this number, as I could see only one side of the roofs. 

 Many others kept continually arriving, and I noticed that all 

 came from one direction, namely, from the north-east, exactly 

 from the same quarter whence I observed a large flock of 

 fieldfares {Turdus pilaris) in the first week in November. I 

 have no doubt the wagtails were migrating, for they seemed 

 tired and glad to rest, and I need scarcely remark that tliey 

 are not as a rule gregarious in their habits. Mr Gray informs 

 me he has observed similar migrations in the west of Scot- 

 land, and Mr Scot-Skirving says he once saw some two 

 hundred of these birds resting on the roof of the General 



