NATURAL HISTORY SOCIETY OF GLASGOW. 55 



The dates of arrival in Egypt are copied from my friend Mr J. H. 

 Gurney's " Eambles of a Naturalist in Egypt," 187G, p. 112. The 

 comparison, I believe, will be found in some degree useful, as there is 

 an extreme probability that many even of the individual birds, not 

 to mention species, which pass down the Nile, continue their flight 

 northward through the plains and valleys of Southern Eussia and 

 descend the valley of the Petcliora. Corresponding with me on 

 the subject of migration, J\lr J. H. Gurney writes as follows : 

 "The comparison of your dates and my Egyptian ones on the one 

 hand, and of my Algerian ones with English ones on the other, 

 must in a measure show the rates at which they travel ; and, if 

 they take longer in travelling in the East than in the West, the 

 greater number of observers in England must be taken into 

 consideration." An additional cause for greater time spent in 

 migration in the East, appears to me to be found in the longer 

 continuance of winter, and consequent scarcity of food, deterring 

 the birds from reaching their far northern breeding limits. I 

 might here quote at greater length from Mr Gurney's interesting 

 correspondence, but I refrain for two reasons — first, because by 

 doing so, I would get beyond the bounds of this connection; 

 and, secondly, because I understand that Mr Gurney intends 

 treating of the subject in a future paper. 



Of course the foregoing table must be ofi"ered for the present in 

 its incompleteness, as there is a great want of tabulated records 

 between Egypt and Ust Zylma, and the time cannot be considered 

 to have arrived in which to generalize more fully, until these 

 records are supplied, or at least until the chain more nearly 

 approaches completion. Those who desire to pursue the subject 

 further — and a very interesting, if intricate one, it is— would do 

 well to consult the following papers : — 



" Die isepiptesen Eusslands. Grundlagen zur Erforschung der 

 Zugzeiten und Zugrichtungen der Vogel Eusslands," by Dr von 

 Middendorff, St Petersburg, 1855 ; and Professor Newton's 



is an occasional visitant in Liguria and Venice; and two specimens are in the 

 Genoa Museum, said to have been killed in Liguria. Lieut.-Col. Irby notices 

 it as having occurred once on the coast of Tangiers ("Ornithology of the 

 Straits of Gibraltar," p. 215). Its absence there would seem a good reason 

 for excluding it from the list of such as would migrate down the Petchora; and 

 I believe that the large gulls seen passing over Ust Zylma (' Ibis,' Jan., 1876), 

 must have belonged to some other species. 



