72 



BOOKS PUBLISHED DURING 1923-4. 



J. Davidson. " A List of British Aphides " (including notes 

 on their synonymy, their recorded distriution and 

 food-plants in Britain, and a food-plant index). Long- 

 mans, Green & Co. (in the press). 



This work has been prepared owing to the great economic 

 importance of aphides in relation to farm, garden and orchard 

 crops, and their possible association with so-called mosaic diseases. 

 Buckton's Monograph on British Aphides was published about 45 

 years ago, and since that time many more species have been 

 recorded and the nomenclature has undergone drastic changes. 



In the present work the species are placed in accordance with 

 the more recent nomenclature. It is divided into four sections. 

 Section 1 deals with the species in alphabetical order together 

 with their food-plants and distribution in Britain. Section 2 

 deals with the genera, including critical notes. Section 3 is a 

 food-plant index, forming a key to Section 1, and Section 4 a 

 bibliography of 360 titles. 



The work is intended to be a reference list and to serve as a 

 general guide to the identification of the species of aphides. 



R. A. Fisher. " Statistical Methods for Research 

 Workers." Oliver and Boyd, Edinburgh (in the press). 



The wide increase in the employment of statistical methods, 

 especially in scientific research, has been accompanied by excep- 

 tionally rapid progress in recent years in the solution of the mathe- 

 matical problems which confront the statistician. Most of the 

 mathetical problems which confront the statistician. Most of the 

 mathematical researches of the author have been undertaken in 

 direct response to the needs of the laboratory worker, and with 

 a view to the development of statistical methods adequate to the 

 practical requirements of biological and agricultural research. 



The aim of the book is to provide the non-mathematical 

 scientific worker with the detailed application of precise statistical 

 methods, which have been available hitherto only in specialised 

 mathematical publications. The methods are illustrated through- 

 out with numerical examples, drawn from recent scientific litera- 

 ture, giving the methods of computation in detail. New mathe- 

 matical tables have been specially calculated for rendering the 

 crucial tests simple and exact. 



THE CROP RESULTS. 

 OCTOBER, 1922, TO SEPTEMBER, 1923. 



The outstanding features of the season October 1922 to 

 September 1923, were the sunless spring and the earliness and 

 seventy of the autumn frosts of 1923. 



The year commenced favourably; October was unusually 

 dry; it had the lowest rainfall figures for this month (0.787in. 

 against an average of 3.06in.) since our records began, so the 

 ploughing and drilling were got well forward. The dry weather 

 continued into November, and with the help of night Frosts which 



