254 JOUENAL OF THE ROYAL HORTICULTURAL SOCIETY. 



in the same direction? In ages past one cannot doubt that en- 

 vironment had precisely the same material to act upon — these had a 

 common ancestor. Or is Nature, perhaps, experimenting ? 



The origin of variations in kind seems still to seek ; or perhaps it is 

 only the origin of the material basis of the power to vary, and from a 

 definite knowledge of what that is we seem to be still far off. 



All the book contains is worthy of careful reading and consideration ; 

 but whatever the origin of variations may have been we are through the 

 careful experiments of many workers being shown that for practical 

 plant breeding the only sure method is to start with the variations shown 

 by individual plants and to breed from individuals, not from promiscuously 

 crossed groups of the same species. 



Here and there the book appears to bear the impress of having been 

 compiled in a hurry, which could be no gain. For instance, the references 

 on p. 94 to the plate are all wrong, and it is stated that " Tamus 

 communis appears to have one cotyledon " when " two cotyledons " was 

 intended. Other somewhat similar mistakes are noticed on p. 8, p. 52, 

 and p. 53. 



" The Principles of Microscopy." By Sir A, E. Wright, M.D., F.R.S. 

 8vo., 250 pp. (Constable, London, 1906.) 21s. net. 



This is a highly technical manual intended for those who are willing 

 to make microscopy a matter of intellectual study. Everyone who uses 

 the microscope seriously should no doubt do this, but, unfortunately, the 

 time at the disposal of most does not permit of studying the instrument 

 so elaborately as the author would have one do, and instead the student 

 has to be content with rule-of-thumb methods and the experience gradually 

 gained by trial and error during the progress of his work. But for 

 those who wish to obtain a thorough knowledge of the fundamental 

 principles underlying the development of proper images in working with 

 the microscope there is no better guide than the volume before us. 



"Pronunciation of Plant Names." By Rev. C. Butler, M.A. Small 

 8vo., 94 pp. (Gardeners' Chronicle, London, 1909.) Is. net. 



The pronunciation of plant names often presents difficulties and 

 particularly in regard to which syllable should be emphasized. With 

 this guide to hand no one need be at loss. It is of convenient size 

 and contains all the generic names that are likely to be met in even 

 the largest garden. While, unlike the admirable list in Nicholson's 

 "Dictionary of Gardening," classical usage is departed from in some 

 names, as Anem'one, the author has probably followed the better course 

 in adopting the more popular pronunciation. The vexed question also as 

 to how far local pronunciation should be followed in generic names 

 derived from personal names is got over by retaining the local pro- 

 nunciation, (though not always completely). Thus Halesia is Hal'-zi-a, 

 Stokesia, Stok'-si-a, Heuch&ra, Hoi'-kera, and so on. The author does 

 not attempt Tchihatchewia ! 



The list is very free from errors in the generic names themselves, 

 though " Absinth' 1 (p. 1) should have been Absinthium, and " JEJsch- 

 scholizia " (p. 33) was originally spelt without a "t," as it is in "Index 



