446 



NATURE 



[OCZOBER 5, 191 1 



new methods really are an improvement on the old. 

 Egypt, old as she is, has to adapt herself to the 

 changed economic conditions of the world, and the 

 problem before her agricultural advisers is funda- 

 mentally the same as in new countries, though in its 

 details more complex. 



The book before us is the second volume of the 

 complete work, the first having been reviewed in 

 these columns about eighteen months ago. It deals 

 with individual crops, with farm pests and farm 

 animals, and its object is to present the student with 

 a general summary of the work done, and the in- 

 formation collected and sorted out, by the experts 

 attached to the various agricultural institutions in 

 the country. The writing of each section of the book 

 has been entrusted to one man, generally one who has 

 done much work on the subject, so that the volume 

 consists of a detached series of contributions. It is 

 therefore extremely useful for the expert who can 

 evaluate the various chapters, but it has not quite 

 the organic unity desirable for a student's text-book. 

 Indeed, it is, in any case, rather large for an ele- 

 mentary student, and the editors will probably find 

 advantages in drawing up an abridgment of the 

 whole work for general use, leaving these larger and 

 more authoritative volumes for the advanced student. 



Cotton is at present the crop to which the Egyptian 

 looks for profit, and where it can be grown everything 

 else is made subsidiary to it. If the land will grow 

 cotton every two years so much the better; but Mr. 

 Cartwright, who has charge of this section, enters a 

 wise caution against overcropping : — 



"Egypt depends on the quality of its staple for its 

 position in the cotton world. This quality of staple 

 is intimately bound up with the fertility of the land, 

 and any loss of the second will almost certainly be 

 accompanied by deterioration in the first." 



A common rotation is cotton, berseem, wheat ; 

 berseem being the Egyptian clover (Trifolium alex- 

 andrinum), which keeps up the supply of humus in 

 the soil, thus counteracting the effect of the ex- 

 tremely rapid decomposition going on. 



The wheat is mainly of the durum type. Red, 

 white, bearded, and beardless varieties can all be 

 found, and the samples are usually very mixed in 

 quality. Wheat forms an important crop in basin 

 cultivation; indeed, the red wheats from the Upper 

 Egypt basins are considered the best type. In Lower 

 Egypt wheat is grown under irrigation as a winter 

 crop. 



In Upper Egypt sugar cane is often the basis of the 

 rotation instead of cotton, the course being sugar 

 c; ""'. sugai - . m. followed by doura, wheat 



with or without doura; sometimes, however, the cane 

 is only grown one year, and the wheat is replaced bj 

 a bare fallow. The two great classes of cane in 

 general cultivation are Beladi, for long the commonest 

 grown, and Roumi, now replacing the older class be- 

 cause of higher producing capacity. Ordinarily 

 sugar obtained is 10 to 15 per cent, of the weight of 

 the cane, about 2^5 per cent, being molasses. Doura 

 or maize is an extremely useful crop for the fellah. 

 Its thinnings supply a large quantity of green food 

 for his cattle when "keep" is scarce; its grain sup- 

 NO. 2l88, VOL. 87] 



plies him and his family with food; moreover, it 

 responds well to liberal treatment. 



Fungoid diseases are ably dealt with by Mr. Balls, 

 who has, on the whole, a very cheerful account to give 

 of the cultivator's lot. 



"The immunity of the important cultivated plants 

 from disease induced by fungi is most remarkable ; 

 berseem and maize, although g. own in enormous 

 quantities, are practically tree irom disease; wheat 

 only bears rust-pustules commonly after the flowering 

 period; and although cotton is inhabited by four 

 common fungi, it is yet attacked by them at such 

 times as to be but little affected thereby." 



Hut Mr. Balls will not leave the cultivator to be 

 lulled into a false sense of security : this happy im- 

 munity, he insists, is not entirely due to climatic 

 conditions, although it is in part ; thus the high tem- 

 perature is unfavourable to fungi, and the unvarying 

 character of the climate enables the pathologist to 

 know exactly what to expect. 



On the other hand, insect pests are numerous and 

 do a good deal of damage. Mr. YVillcocks, who 

 writes this section, inclines to the belief that they are 

 more or less indigenous. Their life-histories are 

 being steadily worked out and remedial measures 

 designed. But it is not always easy to apply 

 remedies in practice. The psychology of the cultivator 

 counts for much, and Oriental fatalism is a bar to the 

 taking of active precautionary measures. The culti- 

 vator always hopes that Providence, or at least 

 Government, will do something, but does not himself 

 do what the Western man would do at once. 



Perhaps the cotton boll-worm is the most serious 

 pest, but the cotton worm (Prodenia littoralis), the 

 small green cotton worm (Caradrina exigua), and the 

 cut worm (Agrotis ypsilon) also do harm, not only to 

 cotton, but to other crops as well. 



Farm animals are dealt with by Mr. McCall. The 

 native cattle are described as races of Bos indicus, 

 but have not undergone artificial selection and im- 

 provement, like the European races of Bos taunts. It 

 is considered that some very fine strains could be 

 produced by proper breeding. 



The book concludes with tables of u 

 and some good illustrations of live stock. Altogether 

 it will be found very helpful to all who are interested 

 in Egyptian agriculture. E. J. R. 



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THIS book is an elaboration of lectures which the 

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