ORIENTAL CHIMNEY SWALLOW. 87 



established in theory, and is so variably demonstrated in practice, that it 

 gives no bounds to capriciousness." 



"In short, are local forms one and the same species? But is not that 

 a name without all philosophical or physiological consideration? Perhaps 

 all the better if philosophy or physiology stood on weak ground. A 

 distinction founded on fact is at least remembered by a matter of fact.* 

 Would it not be advisable to make this matter of fact certain before we 

 dispute about an idea? To do this we must know where the white and 

 rust-coloured Swallows are known to dwell distinctly. How far, and in 

 what statistic relation, the one form extends into the territory of the other, 

 and in what relation there is a proportion between the two forms. "We 

 might then help each other to solve this riddle, and then we shall have 

 no difficulty in being certain about the name." 



This paper I think clearly establishes the fact of the identity of the 

 variety which is the subject of the present notice with the Chimney 

 Swallow. Thei/ breed together. Their habits and nidification are 

 similar. They only differ in the colour of the abdominal plumage, in 

 having a brighter black on the back, and perhaps a broader black collar 

 round the neck. 



The specimen sent me by the Rev. Canon Tristram, which I have 

 figured, and the measurements of which I have given in my diagnosis, 

 was killed in January, 1860, in Egypt, by W. C. P. Medlycott, Esq. 



The plumage above is glossy black; below dark chesnut, with a broad 

 black collar round the neck. Each of the tail feathers has a white spot 

 on its inner web, giving the appearance of a crescentic band when viewed 

 from beneath. 



It has also been figured by Audouin, in plate 4, fig 4, of his "Expedi- 

 tion to Egypt.^' The drawings in this work were done by M. Savigny, 

 after whom Stephens, in his edition of "Shaw's Zoology," named the bird. 



* I append ttie German text of this passage: — "Oder enlich gar Localformen ein 

 und derselben art ? Aber ist das nicht ein ISTame oline alle tiefere philosopliisclie 

 oder pliysiologische Bedeutung? Vielleicht um so besser, wenn die Philosoph.ie 

 oder Pliysiologie auf scbwachen Fussen steht. Eine thatsachliche Bezeiclmung 

 erinnert docli wenigstens an einen Thatbestand." 



