Letters, Extracts, Notices, §c. 171 



catalogue of the collection was printed at Southampton in 

 1894. It enumerates specimens of 281 species, and is 

 arranged according to the B. O. U. List. 



Proposed Expei'iment on Bird-migration. — We are requested 

 by Herr J. Thienemanu, the Director of the Ornithological 

 Station at Rossitten, on the Baltic coast of East Prussia 

 (cf. Bull. B. O. C. xi. p. 68), to call the attention of British 

 ornithologists to an experiment, as regards the migration of 

 birds, which it is proposed to carry on there. Every year 

 during the two migration- seasons hundreds, and, in some 

 years, thousands, of Crows (Corvus corone and C . frugilegus) 

 are caught alive in nets by the fowlers at Rossitten. These 

 birds are to be liberated, each with a small metal ring bearing 

 a number and date attached to one foot. Persons who capture 

 or kill any of these marked birds are requested to return the 

 foot and ring to the u Vogel-warte, Rossitten, East Prussia/' 

 sending with them an exact note of the date and place at 

 which the bird was shot or captured. It is quite possible 

 that some of these birds may wander as far as the shores 

 of Great Britain. If this should happen we hope that Herr 

 Thienemann's request may be complied with. 



A record will be kept at Rossitten of the feet and rings 

 returned, and it is expected that some useful information on 

 the migration of birds may result from this experiment. 



Proposed new General Work on Birds.— M. P. Wytsman 

 (of 108 Boulevard du Nord, Brussels) has sent us the pro- 

 spectus of a new work to be called ' Genera Avium/ and to 

 be carried out on the same plan as his ' Genera Insectorum/ 

 which is now in course of issue. The size adopted will be 

 a large quarto, " each family of birds being published sepa- 

 rately with separate pagination." It will be illustrated by 

 plain and coloured plates, and will be written in English. 

 M. Wytsman claims to have secured the assistance of a 

 " Committee of the best Ornithologists in the world." The 

 issue of the ' Genera Avium ' will be commenced as soon as 

 the names of 150 subscribers have been received. 



