October 28, 1909] 



NA TURE 



535 



by heating the loess at 1300° C. to 1350' C. The loess 

 appears to contain abundant minerals that characterise 

 volcanic lavas. The analyses given show a silica per- 

 centage of about 66 for the debatable scoria; and " baked 

 earths," and of only some 57 for the specimens of loess; 

 but the latter loses some 13 per cent, of water, against 

 4 or 5 per cent, from the former materials. Ducloux 

 opposes the suggestion of Ameghino that alkalies from 

 the associated vegetation, burnt up with the loess, have 

 entered into the composition of the scoriaceous matter. 



H. Bucking's petrographic contribution (p. 185) should 

 certainly have been illustrated. The writer, after micro- 

 scopic examination, has no hesitation in classing the 

 scoria; as ordinary andesites. He traces volcanic lapilli 

 in a " baked earth " from " Chapadmalal," and describes 

 features in this material and in others sent to him which 

 suggest a laterisation of volcanic dust. 



Dr. Ameghino's paper, published in November, 1908, 

 is largely stratigraphical. The beds of Monte Hermoso 

 (p. 344) are here held to be much older than the Pampas 

 formation, on account of their absolutely distinct fauna. 

 If. then, man " or his precursor " is responsible for the 

 " baked earths " found among them, the human race in 

 South America may be traced back further than even 

 Ameghino had previously supposed. We gather that this 

 paper was well advanced before the issue of that by Outes 

 and Ducloux, for .Ameghino has since found it necessary 

 to emphasise still further his views on the " baked earths " 

 in a specially written memoir, in both French and Spanish, 

 entitled " Productos piricos de origen antr6pico en las 

 formaciones neogenas de la Republica Argentina " {Unales 

 del Mtiseo uac. de Buenos Aires, tomo xix., p. i ; pub- 

 lished February 17). He points out that the analyses of 

 Ducloux merely show that the alleged volcanic cinders 

 might have been formed from the fusion of the earth in 

 which they lie, which is precisely the point that Ameghino 

 wishes to establish. But it is not clear that the fused 

 products (p. 17), prepared by Ameghino himself at 950° 

 to 1000° C, have been submitted to microscopic examina- 

 tion, or that they exhibit the felspars and other associated 

 minerals found by Bucking in the scoria. 



.Ameghino (p. 19) states that certain burrows formed as 

 nests by the bee Ancyloscelis analis occur in the " baked 

 earth," which must therefore have been burnt after the 

 formation of the nests. Presumably this bee must also 

 be transferred to the Miocene period if this argument is 

 to be sustained. The paper concludes with a statement 

 of how Outes and Ducloux failed to bring forward at 

 Santiago, in Chile, a promised refutation of Ameghino's 

 reiterated views. We may be happv, perhaps, if they 

 consider that enough has now been said. While Florentino 

 Ameghino does not seem to appreciate sufficiently the 

 changes induced in rocks by laterisation, his critics have 

 certainly not utilised to the full the resources of modern 

 petrology. Probably some independent worker will 

 ultimately arrive upon the scene, and we venture to think 

 that he will confirm the views of Steinmann, Outes, and 

 Ducloux. The widely distributed materials which have 

 aroused so much discussion are hardly likely to add to 

 our knowledge of the antiquitv of man in South America. 



G. A. J. C. 



AGRICULTURE AT THE BRITISH 

 ASSOCIATION. 



TN view of the outstanding importance of agriculture in 

 -'■ Manitoba, it was decided to concentrate attention on 

 a few of the fundamental problems of the North-west and 

 to discuss them as fully as possible both in the subsection 

 itself and in joint meetings with other sections. Such 

 joint discussions are particularly valuable, because the 

 problems in agricultural science are highly complex, and 

 have generally to be dealt with by men working away from 

 large university centres and only occasionally coming into 

 contact with pure men of science. Only those who have 

 had to work under such conditions know what it means 

 to attempt research work in small laboratories in the 

 country without the stimulus of the research atmosphere, 

 often, indeed, with the drag of a considerable amount of 

 routine work and little opportunity of discussing the 



NO. 2087, VOL. 81] 



problena with the chemist or botanist who could throw 

 much light upon it. Under present conditions almost the 

 only opportunity the agriculturist has of meeting his fellow- 

 workers in the region of pure science is at the British 

 Association meeting. For this reason agriculturists are 

 awaiting with no small interest the outcome of the pro- 

 posal made last year, and carried forward another stage 

 this year, that agricultural science shall form a definite 

 and permanent part of the British Association programme. 



In his presidential address Major Craigie dealt with the 

 future wheat supply of the world, and showed that there 

 was no reason for the gloomy apprehensions that have at 

 times been raised, and particularly by Sir W. Crookes at 

 Bristol in 1898, as to whether or not population would out- 

 strip wheat production. The address is printed in extenso 

 in Nature CSeptember 30). 



Dr. W. Saunders gave an account of the experimental 

 farm system in Canada. The central farm is at Ottawa, 

 where the scientific staff reside. There are eight sub- 

 sidiary stations situated at various points between the 

 Atlantic and Pacific coasts, viz. at Prince Edward Island, 

 Nova Scotia, Branden (Man.), Indian Head and Rosthern 

 (Sask.), Lacombe and Lethbridge (Alta.), Agassiz (B.C.). 

 At each of these a scheme of experiments drawn up at 

 Ottawa is carried out under the supervision of an experi- 

 enced superintendent ; different varieties of crops suited to 

 the district and different methods of management are all 

 investigated, and the results published as widely as possible. 

 Any abnormalities or matters of general interest that may 

 require further elucidation are examined in greater detail 

 at Ottawa. 



The possibility of extending the food production of 

 Canada was discussed at a joint meeting with the 

 Economics Section, papers by Prof. Brigham, secretary of 

 the Association of .American Geographers, and Prof. 

 Mavor, of the Toronto University, forming the text. The 

 possible wheat area of the three provinces Manitoba, 

 .Alberta, and Saskatchewan has been put at 173 million 

 acres, and the possible output at 317^ million bushels, 

 which estimates are not at all accepted by the optimistic 

 westerners. Prof. Mavor, however, points out that wheat 

 cultivation cannot continue to be the mainstay of 

 husbandry, but that mixed farming must become more 

 common. Already, indeed, the wheat area is going down 

 in Ontario, and in certain other districts it is not in- 

 creasing so rapidly as the area under oats. Dry farming, 

 which alone could be practised over large areas, is as yet 

 on its trial. The difficulty of forming satisfactory 

 estimates is complicated by the fact that two sets of 

 mutually inconsistent statistics are officially issued, one 

 compiled by the Dominion Statistical Department, the other 

 by the provincial authorities. 



.A joint meeting with the botanical and chemical sections 

 was held for the discussion of wheat problems. An 

 important contribution to the history of the various wheats 

 was made by Dr. Stapf, whose paper was read in his 

 absence by Colonel Train. Hitherto this question has been 

 very obscure, and has formed the subject of much specula- 

 tion. Dr. Stapf has succeeded in applying more precise 

 methods, and in replacing the vague ideas hitherto held 

 by definitely ascertained facts. The factors determining the 

 yield of wheat formed the subject of a paper by Messrs. 

 A. D. Hall and E. J. Russell. Wheat is very dependent 

 on a supply of nitrogenous food-stuff ; indeed, for small 

 increments of nitrogen a more than proportional crop 

 return is obtained. At a later stage the returns diminish, 

 and after a time cease to yield any profit. Phosphates 

 are of less direct importance, but have considerable indirect 

 effect; in particular, they often enable the crop to be 

 harvested at a somewhat earlier date, and thus they tend 

 to extend further northwards the region of profitable pro- 

 duction. It was also shown that wheat is capable of with- 

 standing drought conditions, and is therefore a crop 

 adapted to dry regions. Mr. F. T. Shutt discussed the 

 influence of environment on the composition of the grain. 

 Whilst not prepared to maintain that the percentage of 

 nitrogen, phosphoric acid, or potash in the soil would 

 appreciably affect the percentage of these substances in 

 the grain, he nevertheless showed that the composition of 

 the grain was influenced by its surroundings. Soil 

 moisture affects the quantitv of nitrogen present ; on 



