15 



it necessary to have recourse to a country extending beyond the 

 Urals to sustain even the millions of Herr Gatke, as he himself 

 suggests. 



How are we to account for the accumulation of these vast 

 flocks, if we accept the theory that all on setting out from their 

 nesting stations travel in a rigidly maintained westerly direction 

 and in a broad column corresponding to the latitudinal area of 

 the latter ? Except at the periods of migration the Hooded 

 Crow is not a particularly gregarious species, and though con- 

 siderable numbers may be present in a small district, yet at their 

 winter quarters small parties, rather than flocks, are met with 

 as a rule. With regard to the breadth of these flights, the most 

 that has been proved is, that on a certain occasion, viz., October 

 24th, 1884, the present species, in company with Books and 

 Jackdaws, was observed to be passing over and near Heligoland 

 in vast numbers, and in a flight having an ascertained frontage 

 thirty-six or forty miles in extent, though we are not told this 

 was an unbroken front. Now no country, due east of Heligoland, 

 of this breadth, even if it extended as far as the Yenesay, would 

 have been large enough to have produced the millions comprising 

 this flight. Herr Gatke also further attempts to prove that 

 this migration front covered a vastly greater breadth. At the 

 same time, he writes, that an extraordinary migration was taking 

 place " over the North Sea, on the eastern coast of England and 

 Scotland up to the Orkney and Shetland Islands." On referring 

 to the "Eeport on the Migration of Birds for 1884," it will be 

 found that whilst there certainly was a large movement in 

 progress on the east coast of England, within or around a latitude 

 corresponding to that of Heligoland ; further north, however, 

 the numbers arriving were insignificant and not more than the 

 normal. In support of this statement those portions of the same 

 report relating to the east coast of Scotland may be quoted. On 

 p. 28 we read — " In autumn, a more decided movement of 

 Hooded Crows (this in comparison with spring, when less than 

 usual were observed). Eecords from Sumburgh Head, North 

 Eonaldshay, Pentland Skerries, Girdleness and Isle of May (none 



noted at Bell Eock) Decided rush between October 



11th and 26th at Pentland Skerries (14th), and at Isle of May." 



