374 Recently published Ornithological Works. 
attributed to the result of the exertion caused by the capture 
of struggling insect-prey, which induces the energetic bird 
to erect its frontal feathers ! 
We will reserve our remarks on the general Avifauna of 
Guiana until the completion of the work by the issue of the 
second volume, which, we understand, has already reached 
Holland in manuscript, and will, we hope, be published with¬ 
out much delay. We are not sure that the authors have done 
well in writing in their native language. It is highly 
patriotic, no doubt, but we fear that it will interfere with the 
circulation of the book. English is well understood by all 
educated Hollanders, and especially by those who read 
scientific books. 
We understand that the collection of bird-skins made by 
the authors has been acquired by the Tring Museum, 
and that the accompanying series of eggs (which contains 
specimens referable to 273 species) has been presented to 
the Leyden Museum. 
43. Pycraft on Birds. 
[A Book of Birds. By W. P. Pycraft. London, 1908. Pp. i-viii, 
1-155, with coloured plates and text-figures.] 
Mr. Pycraft has invariably something interesting to relate 
with regard to Ornithology, but we consider his talents 
wasted in writing letterpress to accompany the thirty inferior 
coloured plates contained in this volume, which consists of 
a general survey of the principal groups of Birds, with 
special reference to those of Britain and the rest of Europe. 
The forms included are for the most part selected with the 
view of bringing out the differences in anatomical structure, 
and in this connexion the author warns his readers that 
similarity of appearance does not necessarily imply close 
relationship. The instances are well chosen; but for the 
general public it might have been better to have reduced 
the number of species and treated the remainder more fully, 
as may be seen in the case of the Megapodes and Cuckoos. 
Nearly thirty pages are devoted to an admirable Introduc¬ 
tion, which, after touching upon the descent of Birds from 
