Vol. XI. No. 278. 



THE AGRICULTURAL NEWS. 



405 



TEE COTTON I'LAXT IX EGYPT. By W. Law- 

 rence Balls, M.A. MatiiiillaH dc Co. 5s, net. 



In this book, Mr. Balls has brought together in 

 a condensed form a review of his researches made upon cotton 

 plants in Egypt, and the outcome is striking and valuable, 

 resulting in a book which, while appealing strongly to 

 everyone interested in the problems attendant on cotton- 

 growing, will claim the attention of students of plant 

 physiology and plant-breeding generally. Problems of the 

 broadest interest are dealt with, while the methods of 

 investigation are such as command admiration, and the 

 results constitute valuable additions to knowledge, not only 

 as regards the cotton plant, to which they immediately apply, 

 but also in relation to plant physiology in general. 



The book is written in an extremely condensed style, 

 especially in its earlier chapters, and indeed lornis an excellent 

 summary of valuable work which serious students will do well 

 to supplement by reference to the author's numerous papers, in 

 which much of the information is given in greater detail. A 

 good bibliography appearing at the end of the work 

 facilitates such reference. 



We are told that the investigations began as genetics but 

 necessarily extended into physiology. We are grateful that 

 this happened, for much of the physiological work is of the 

 most fascinating and stimulating nature, so that one asks 

 oneself why similar work should not be carried out on mnny 

 more of our staple crops, both of the tropics and of temperate 

 regions, feeling sure that results would follow which would 

 ultimately have a bearing on crop production. 



It is impossible in the space of a brief review of a book, 

 which is itself an extremely condensed epitome, to give 

 consideration to more than a very limited number of points 

 of interest. The chapter dealing with fertilization, cytology 

 and embryology is a model of close and luminous writing, 

 containing much that is of service to the investigator. 



The work on development and environment brings to 

 light a number of most important facts, some of them of an 

 unexpected character: for example 'the sunshine effect', in 

 connexion with which it is established by a fascinating series 

 of observations that direct sunshine completely inhibits 

 growth. The manner is which the fact is established, the 

 careful observations, the ingenious apparatus employed and 

 the careful reasoning will appeal strongly to plant physiolo- 

 gists. In the same way the observations on the growth and 

 functions of the root are full of points of profound importance. 

 The first matter that strikes one is the rapidity of growth of 

 the root of the cotton plant and the enormous volume of soil 

 ultimately occupied by it, whereby under field conditions even 

 under circumstances of wide planting, there is so much root 

 interference that the plants behave as if 'potbound'. 



The relationship of the root system to the water table is 

 completely worked out; it is shown that a deep water table is 

 essential, and that a rise of the water table to the roots under 

 Egyptian conditions is: 'deadly in July, prejudicial in Septem- 

 ber and almost harmless in December.' The relationship of 



this to the changes in the level of the water table induced by- 

 inigation has been worked out by the author and his col- 

 leagues so that, as he remarks, 'the preliminary solution of 

 one of the neatest problems ever set to agricultural science 

 has thus been achieved on a croj) which is worth 20 to 30 

 millions of pounds per annum.' 



The manner in which the problem relating to the loss of 

 young cotton seedlings was handled constitutes another fine 

 piece of biological work. The lo.ss was attributed by cottoa 

 growers to the effect of cold and fog ; it was shown to be due 

 to a specific fungus whose growth and development are 

 absolutely dependent on temperature in such a manner that 

 the injury to the young seedling.s ceases when the tempera- 

 ture rises to 37°C. For an account of the interesting observa- 

 tions and reasoning, and the practical suggestions for 

 dealing with the trouble, the reader must refer to the book 

 itself. 



The observation.s on boll-shelling, with the discussions 

 on the mechanism and cause.s of the shedding, will be read 

 with much interest. It is shown that the principal cause of 

 the trouble in Egyiit is root asphyxiation. The observations 

 recorded will doubtless stimulate other workers to a closer 

 study (if the causes that may be operative in their own fields 

 of experiments. 



The short chapter on the cotton fibre contains valuable 

 additions to knowledge which will find application va the 

 work of other experimenters. 



A considerable portion of the book is devoted to the 

 study of questions of heredity; in this connexion a large 

 amount of valuable work has been done, the results of which 

 are briefly recorded In most instances it is shown that the 

 controlling factors in the cases studied are of a complex 

 character, so that a vast amount of work remains to be done 

 in order to elucidate them. Some instances of fairly simple 

 inheritances are brought to light, but even these are so- 

 masked by the effects of environment as to be difficult of 

 perception. The explanation given of the underlying facts- 

 relating to the inheritance of seed weight by 'clearing away 

 the lumber brought in by autogenous fluctuation' will appeall 

 to workers in this field. 



Difticult and obscure as are the problems of heredity- 

 connected with cotton, the author states his conviction that: 

 'the hybrids studied are subject to Mendel's Law of Segrega- 

 tion often obscurely — on account of defective methods— but 

 none the less certainly,' and: 'that there is no doubt as to 

 the formal inheritance of various characters in cotton crosses, 

 even when such inheritance seems most dependent on simple 

 chance.' 



A picture conjured up by the author may fitly come 

 near the end of this notice. 'The outcome of such, 

 deductions must be that the colonial agriculturist of 

 the near future will no longer carry a bag of seed, 

 searching for a district in which it will grow to the 

 consumer's liking but will choose his district first and 

 then manufacture a cotton plant to suit it.' But it may be 

 added that he will need the co-ooeration of such investigators 

 as the author, backed up by adequate means for investigating- 

 things which may appear to have little application to the 

 practical problems they may ultimately aid in solving; and 

 that work such as this under review is a powerful appeal for 

 the endowment of research. 



In the Comptes Rfiidus de V Acadt'inie des Sciences, 1912^ 

 p. 891, an apparatus is described for growing plants with 

 their roots in a sterile mediutu, while the stem and leave*, 

 are free in the air. 



