100 BRITISH BIRDS. [vol. x. 



Trans, of the North Staffs. Field Club, Vol. XXVII., pt. 2. 

 pp. 5-7 (1893). The late F. Coburn published a pamphlet 

 of 12 J)]?, on the " Ornithology of the City of Birmingham " 

 (1895), as well as several articles in the Zoologist on ornitho- 

 logical subjects. We fail to find any reference to Mr. Warde 

 Fowler's little book on Kingham Old and New, which con- 

 tains a chapter on the Bird-life of the district. For 

 '' Magdalen " read " Magdalene " (p. 234, line 14 from above). 

 Mr. B. A. Carter we take to be Miss B. A. Carter (p. 121). 

 Mr. R. W. Chase's home is now at Bewdley and not at King's 

 Norton. Mr. R. Drane gave a good account of the bird-life 

 on 8komer, under the curious title of "A Pilgrimage to 

 Golgotha " (Bep. and Trans, of the Cardiff Nat. Soc, XXXI., 

 1898-99). The list of birds in' Stephen Glover's History of the 

 County of Derby is not the work of that writer, but was founded 

 on Pilkington's list, with additional notes by 0. Jewett. 



The strongest point in this book is the care and scrupulous 

 detail with which the older writers have been treated. Here 

 Mr. Mullens is in his element, and his work stands without 

 a rival. Our readers will not have forgotten the series of 

 exhaustive articles on the works of the early British Ornitho- 

 logists, Avhich have appeared in previous volumes of this 

 journal. We note with pleasure that the authors propose to 

 incorporate any additional information which may come to 

 hand during the process of publication, in a Supplement, and 

 congratulate the authors on the successful beginning of a 

 task of enormous difficulty. F. C. R. Jourdain. 



LETTER. 



ON INCUBATION. 



To the Editors of British Birds. 



Sirs,- — In Mr. J. H. Owen's second article on the Sparrow-Havvk 

 (antea, p. 26) he states that, if the hen is not incubating she will " almost 

 always be on the nest, not covering the eggs but sitting beside them." 

 This guarding of the eggs without incubating them is luidoubtedly 

 uncommon, but occurs in some other Raptores. In the case of the 

 nearly-i-elated Cooper's Hawk of North America, Mr. W. De W. Miller 

 of the American Museum of Natural History, New York, informs me 

 that incubation does not commence with the first egg (in many cases 

 at all events), but that the bird is always at hand to protect them. 



With regard to the incubating habits of the Jackdaw (antea, p. 40) 

 I have not my notes by me, but it is certainly usual for this species 

 to commence to sit as soon as the first egg has been laid. Mr. Owen 

 says, " £ome sets were all fresh " ; but if the clutch had just been com- 

 pleted the embryo would not be visible in the eggs first laid, even 

 though incubation had commenced with the first egg. The formation 

 of a small micleus on the yolk being all that occurs in the first five 

 days of incubation in many species, this easily escapes observation. 



Eric B. Dunlop. 



