660 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



calling the smut of oats caused by Ustilago laevis Ustilagose instead 

 of "covered smut"? or "dry rot" of sweet potatos " Lasiodiplo- 

 diose"? However, not science, but popular usage must determine 

 whether such names stand and come into the common tongue. 



This innovation does not detract from the excellent advice given on 

 the treatment of the diseases dealt with or the clear descriptions of the 

 symptoms of disease, and here we have no room to enter a complaint. 

 Naturally, the emphasis laid upon different diseases varies from what 

 would be the case in our own country, but one-time local diseases are 

 apt, by-and-by, in spite of legislation, and sometimes, perhaps, because 

 of it, to become international ; so we may welcome here a full treatment 

 of diseases which are not yet greatly prevalent on this side of the 

 Atlantic. 



There is now no lack of good text-books on plant-diseases in Eng- 

 lish, and though we have not yet such a comprehensive one as the 

 " Handbuch der Pflanzenkrankheiten " of Sorauer, yet the writings 

 of Cooke, Massee, Duggar, W. G. Smith's translation of Tubeuf's 

 book, and Ward's " Disease in Plants " give us reliable information 

 regarding plant diseases due to fungi and their treatment, and the 

 present adds another to the list. 



" The First Principles of Heredity." By S. Herbert, M.Sc. 8vo., 

 vii + 199 pp. (Black, London, 1910.) 5s. net. 



In the preface we read : " I claim no originality for the contents of 

 this book. Its purpose is to supply in a simple and yet scientific 

 manner all that may be desirable for the average intelligence to know^ 

 about Heredity, and related questions, without at the same time 

 assuming any previous knowledge of the subject on the reader's part." 



We have, within the past four or five years, reviewed a large 

 number of books dealing with heredity in this Journal, and among 

 them are at least two or three covering practically the same ground as 

 is covered by the present one. This certainly gives a full outline of 

 the various theories that have been brought forward to explain the 

 facts of heredity, and of some of the facts that need explanation; but j 

 such sentences as " The order of the ontogenetic stages of the j 

 embryogenesis is due to the inherent forces in this structural arrange- ! 

 ment of the germ-plasm " suggest that some of the book might have 

 been made more " simple " — fortunately, there is a glossary. A con- 

 siderable amount of space is devoted to the consideration of Mendelism, 

 and though we read much about " dominance " and " allelomorphs," 

 and so on, yet we find no mention of Mr. Hurst's suggestion of the true 

 explanation of observed phenomena being due to " presence "or | 

 " absence " of determinants in the germ-plasm (see this Journal, 

 p. 24). In so recently published a book one would look for mention at 

 least of such a suggestion as this, which to the ordinary intelligent 

 person, is certainly more illuminating than the abstract conception of a 

 " recessive character," which is a character of the individual due to 

 lack of something else, not a character in itself such as the " dominant 

 character " is. 



