1916] CURRENT LITERATURE 159 
development and heredity. The fifth chapter, dealing with the ‘Control of 
heredity: eugenics,’ is a somewhat conventional treatment of an important 
subject. The sixth chapter, entitled “Genetics and ethics,’ has been com- 
mented upon previously. 
A useful bibliography, een and index complete the volume, which, 
though possibly not so well s some for textbook use, is, in the reviewer’s 
opinion, probably the best Cebit of genetics for the non-scientific 
reader.—H. H. NEwMAN 
Bacteria and plant diseases 
The third volume of Smtru’s Bacteria in relation to plant diseases con- 
tinues the treatment of the vascular diseases which was begun in the second 
volume with a discussion of the wilt of cucurbits, the black rot of crucifers, 
and the yellow disease of hyacinths. In the present volume a full treatment 
is accorded Cobb’s disease of sugar cane, Stewart’s disease of sweet corn, the 
Grand Rapids tomato disease, the brown rot of the Solanaceae, and the wilt 
diseases of tobacco. These diseases have been extensively investigated by 
the author himself. The accounts, therefore, contain not only a complete and 
critical discussion of the literature, but also embody the author’s own results 
and present his viewpoint at the time of the writing. 
In addition to these diseases, to which the greater part of the volume is 
devoted, a number of diseases of minor importance, or such as have not been 
seen by the author, or whose right to be classed as bacterial diseases has not 
been definitely established, are considered. Among these may be mentioned 
several diseases of the sugar cane, some of which are probably identical with 
Cobb’s disease, a disease of amaranths, a wilt of the peanut, a disease of orchard 
grass, various vascular diseases of the banana, and two diseases of the potato. 
T he status of many of these is still obscure. That some of them, as the various 
of the sugar cane and the many wilts of tobacco and other solanaceous 
plants, are not all distinct is the belief of the author, but, in accordance with 
his custom, each disease independently described is kept separate until its 
identity shall have been establish 
The book may well be said to ‘he a record of the present status of our 
knowledge of the diseases of which it treats. At the same time it bears internal 
evidence i in the many changes during the making that this status is rapidly 
ifting. By bringing together and classifying the vast mass of scattered and 
fragmentary facts relating to the subject, the author has laid bare the gaps 
in our knowledge and has thus pointed the way for further research. Many 
gaps have been filled by the author’s own work, but that much remains to be 
done before even the morphological and etiological phases of the subject shall 
have been cleared up is shown by a glance through the chapters on the brown 
MITH, ERwIN F., Bacteria in — to plant diseases. Vol. III. pp. viii+-309. 
i 47. figs. 138. Washinbtoe. D.C. 1914. 
