510 SCIENCE PROGRESS 



the bulk is occupied by a consideration of the individual types of vegetables and 

 their particular needs. 



Those little details which are so helpful to the amateur, and for which even 

 the professional may sometimes consult a text-book, are apt to be omitted. For 

 example, tomato culture, which is treated of at length, contains no directions as 

 to the pinching out of buds, or the desirability, under certain conditions, of 

 reducing the foliage. 



A good deal of information is contained between the two covers, but there is 

 an absence of that thoroughness of treatment which is so essential if practice is to 

 be based on a sound knowledge of principles. 



E. J. S. 



Strawberry Growing. By S. W. Fletcher, Professor of Horticulture at the 

 Pennsylvania State College. Rural Science Series. [Pp. xxii + 325] 

 (New York: The Macmillan Company, 1917. Price $1.75 net.) 



This book is a review of the present position of the strawberry industry and a 

 thorough practical guide to strawberry cultivation as it is practised in North 

 America. The first chapters deal with questions of cultivation, such as planting, 

 rotation, tillage, training, mulching, pollination, etc. Then follow chapters on 

 picking and packing, markets, and cost of production, and finally a discussion 

 of certain cultural questions : propagation, varieties, forcing, and other special 

 methods of culture, and diseases. Statistics confined to North America form the 

 subject of an appendix. 



The treatment throughout is thorough, and, with the author's companion 

 on The Strawberry in North America, reviewed in the previous number of 

 Science Progress, the whole field of the strawberry industry is covered. The 

 handling of the soil, the plant and the pickers are all equally well dealt with. It 

 becomes clear from these volumes that the strawberry industry in America differs 

 in many particulars from the industry in Britain. This can undoubtedly be traced 

 back very largely to the greater amount of land available for cultivation in 

 America, with the greater distances between consuming populations, and on 

 the whole less intense cultivation. Some differences can scarcely be explained 

 on this ground, as, for instance, the fact that in England only hermaphrodite 

 varieties of strawberries are employed, while in North America unisexual female 

 plants are also used. The latter varieties appear, however, to be gradually dis- 

 appearing. 



In the matter of pollination the author states, on the authority of Ewert, that 

 " parthenogenesis, or the production of fruit without fertilisation, is common in the 

 strawberry." It is not clear, however, from this statement, whether it is really 

 parthenogenesis or the much commoner phenomenon parthenocarpy, which is 

 meant. The observation that " It cannot be denied that, occasionally, the 

 character of the fruit may be influenced very slightly by the kind of pollen 

 used," is of great importance from a purely scientific point of view, and deserves 

 further investigation, even if instances are rare. 



Although the book only aims at describing commercial strawberry practice in 

 North America, it will be read with the highest interest by those in this country 

 who are interested in the strawberry. 



W. S. 



