126 Eecently published Ornithological f Forks. 



potent of which is temperature ; fourthly, that the predomi- 

 nating distribution of the respective colours is largely con- 

 fined to the faunal divisions of the Eastern United States, 

 and is gradually effecting the subspecific differentiation of 

 the two phases ; lastly, that the Darwinian theory of " Re- 

 production with variation and the survival of the fittest " is 

 well exemplified in Megascops asio. 



6. Lewis on the Birds of Hertfordshire. 



[Notes on Birds observed in Hertfordshire during tlie year 1892. By 

 Henry Lewis. Trans. Hertf. N. H. Soc. 1893, p. 161.] 



Three additions were made to the list of the birds of 

 Hertfordshire in 1892, namely, Aix sponsa, Dafila acuta, and 

 Harelda glacialis, and the total number of the Avifauna was 

 thus raised to 205. Mr. Lewis adds miscellaneous notes, 

 and records the arrival of the migratory species in 1892. 



7. Meyer's Illustrations of Birds' Skeletons. 



[Abbildungen von Vogel-Skeletten. Herausgegeben mit Unterstiitznng 

 der Generaldirection der kciniglicben Samnilungen fiir Kunst und Wis- 

 senscbaft in Dresden. Von Dr. A. B. Meyer. Lief, xiv., xv. (1890); 

 xvi.-xviii. (1892). Folio. Dresden : 1890-92.] 



For several years Dr. Meyer's great work on the skeletons 

 of birds has not been noticed in ' The Ibis,' the last part 

 commented upon having been part xiii. of the series. Since 

 that, five additional parts have been issued, and the work 

 altogether, so far as it has gone, contains 180 plates. We are 

 not of opinion that figures of the whole skeleton afford the best 

 possible illustrations of this part of the bird's structure. A 

 series of the various separate bones placed side by side would 

 in many respects be more useful to the student. At the 

 same time, Dr. Meyer's work, when complete and provided 

 with a good index, will, no doubt, be a very useful publi- 

 cation, as giving a general view of the variations in the 

 osteology of birds. 



8. Meyer on the Birds of German Neiv Guinea. 



[Neuer Beitrag zur Kenniniss der Vogelfauna von Kaiser Wilhehnsland, 

 besonders vom Huongolfe, nebst Bemerkungen iiber andere Papuaniscbe 



