508 Recently published Ornithological Worhs. 
generally available system for the whole of Russia (European 
and Asiatic). The author^s chief object is to encourage bird- 
hunters in all parts of Russia, and especially in the Asiatic 
provinces_, to cultivate Ornithology. He disclaims complete- 
ness for the present work, and refers the reader for more 
detailed information to Prof. Menzbier's book ^ The Birds of 
(European) Russia/ and to the *" Birds of Europe/ by 
Holodkofsky & Lifantief, in course of publication in parts. 
The system adopted in these tables is to co-ordinate the 
distinguishing characters of two types of each variety or 
species, leaving the collector or observer to classify his 
specimens according as these assimilate to one or the other 
type. Intermediate specimens are of great interest from 
various aspects, such as geographical distribution, palseon- 
tology, and the origin of species. To these must be added 
differences due to hybridization (very common among the 
Gallinaceas) , influence of climate, sex, age, and season. 
With these last the tables are not concerned. As a hand- 
book for the Russian sportsman and collector in remote 
parts of the Empire, where books are difficult of access, 
M. Boutourline^s tables will probably be found useful. 
81. Clarke on the Migration of Birds, 
[Bird Migration in Great Britain and Ireland. Fourth Interim Report 
of the Committee consisting- of Prof. Newton (Chairman), Rev. E. P. 
Knubley (Secretary), Mr. John A. Harvie-Brown, Mr. R. M. Barrington, 
and Mr. A. H. Evans, appointed to work out the details of the Observa- 
tions of Migration of Birds at. Lighthouses and Lightships, 1880-87. 
Rep. Brit. Assoc. Glasgow, 1901.] 
This Report contains an account of the migrations of the 
Skylark (Alauda arvensis) and of the Swallow (Hiruado 
7'ustica), worked out similarly to those of former species (see 
*Ibis/ 1901, p. 325) by Mr. W. E. Clarke with his usual 
accuracy and comprehensive grasp of the subject. A serious 
deficiency of data is noted with regard to the South Coast 
of England, but the subsequent visit of Mr. Clarke to the 
Eddystone Lighthouse (' Ibis,^ 1902, p. 246) has resulted in 
the acquisition of much further information. 
