REVIEWS. 68 



The breast, or rather the state thereof in the domestic 

 fowl, is some guide at such a time, but the vent spots are 

 new to me. 



M. C. H. Bird. 



[The subject of "Incubation Spots'' has been much 

 neglected by ornithologists. The most extensive observa- 

 tions known are those of Faber in hi,, work " Ueber 

 das Leben der hochnordischen Vogel," -p. 18f), where he 

 describes their appearance in several different species 

 under the name of "'brood-spots," and endeavours to 

 distinguish between " true " and " false ' ' brood-spots. 

 But much that has hitherto been written on this subject 

 must be discounted ; and this because no distinction was 

 made between areas where the feathers had become simply 

 abraded during sitting, and areas actually concerned in 

 the generation of heat for the purposes of incubation . 



Only the centre of the abdomen is really concerned in 

 this heat production, which is due to the fact that in this 

 I'egion of the body, during the brooding period, the blood- 

 vessels — veins and arteries — become highly congested. In 

 many birds this area is normally feathered, and in such 

 cases, during the work of incubation, the feathers are 

 removed by the beak. In the ducks, which have besides a 

 thick "under-fur "' of down, this down, as is well-known, is 

 used to surround and cover the eggs when the sitting-bird 

 leaves the nest. — Eds.] 



BAER'S POCHARD AS A BRITISH BIRD. 



To the Editors of British Birds. 



Sirs, — In the first number of British Birds, page 14, 

 Mr. Saunders makes certain remarks about the possibility 

 of the record of Baer's Pochard by my brother being more 

 than likely referable to an escaped bird. 



In reply to this, I can only say that if Mr. Saunders' 

 information as to the introduction of Baer's Pochard as an 

 ornamental species to Europe is correct, it must have been 

 since the record in question, for Dr. Ernst Hartert and I 

 made the most minute inquiries at the time. 



We found that the only birds introduced alive into 

 Europe had been the pinioned birds imported by Mr, 

 Frank Finn, and as these — all but one — were alive in the 

 Zoological Gardens, Regent's Park, at the time my brother's 



