?".)fi 



THE AGlilCULrUlUL XEWfc. 



SKtrKMBUS, 2U IdliJ. 



HkaT) Okficb ^ 



;»«f — Barbados. 



EDITORIAL i^U']'^ NOTICES 



'SV-.V 



S^ 



S' 



Letters and matter for publication, as well as all 

 ■ *pecitnen«4 for namir-g, should be addressed to the 

 Ooiumissioner, Imperial Department of Agriculture, 

 VUibivdos. 



All ^^pplications for cc^pijs oi the 'Agricultural 

 News' and other Departmectp.l publications, should be 

 •uldresscd to the Agents, and not to the Department. 



The complete list of Agents will be found on 

 ^htue 4 of the cover. 



Imperial Commissioner of Sir Francis 'Watts, K.C.M.G. 



Agrit^dUtrc fi^ the Weit Indies D.Sc, F.I.C., F.C.S. 



SCIESTIFIO STAFF. 



»S.;-nti,*c Assistant and ^V. R. Dunlop. 



luisiaut Editor ' ' ' . 



Ji. fttnwlogist H. A. Ballou, M.Sc. 



Mytolrxjiit W. Nowell, D.I.C. 



AfUiant for Cotton Research S. C. Harland, B.Sc.+ 



OLERIOAL STAFF. 



A. G. Howell. 

 (h. A. Corbin. 

 J P. Taylor.* 

 t.K. K. C. Foster. 

 ^ypi$t Mi'38 B. Robinson. 



AMtittant Typist Miss W. Ellis. 



A.nutani for PttbUcations A. B. Price, Fell. Jonm. Inst. 



iPiovided by the Imperial Department of Scientific and 



Indvstnal Research. 

 *8ef-(>nded for Military Service, 



Agricultural Items 



<}kUf CUrk 

 Clerieal Assistants 



Vol. XVm. SATURDAY, Si:i'TEMBER 20, 1919. No. 454. 



NOTES AND COMMENTS. 



Contents of Present Issue. 



The editorial in this issue gives various instances 

 of the way in which harm may accrue from the dis- 

 semination of wrong theories. 



An interesting article, illustrated, on the fisher- 

 man-fiah appears on page 2!»:'. 



A first-hand report on a recent tractor demoQstm- 

 ticn ill Barbados will bi; found on page 301. 



ln.scct Notes in this issue comprise two arliclt^s, 

 .iDc on the food of Tiphia and Dampsomi^ris, the .second 

 an insects attracted by smoke. 



Developing British Guiana 



Speeches uiade in J^ondon at a Koyai Coioiii.Hl^ 

 Institute luncheon jjiven in honour of the Demerara 

 delegates on August i:', i:ist. are reported in a recent 

 issue of Tkc Titnrn. 



The statements niailc weiv chiefly repetitions of 

 well-known facts, the uulstamling one being that 

 British Guiana ro<(uir(:s labour. There is little in 

 the speeches to indic.-ile that practical wurk is being 

 done to solve the problem As reported in The Tim.i'ti, 

 it would appear to the bluglish reader that British 

 Guiana iei)uireg European settlers : whereas the real 

 requirement is native labi»ur capable lif doing fieU 

 work on the estates, and cajable of opening up and 

 settling in the interior. 



The possibility of obtaining lahour from India 

 seems remote. It will therefore be necessary to 

 consider possibilities farther east, in (^hiiia and J.apan, 

 and in Africa, where there is a surplus that might be- 

 attracted to British tUiiana, if a scheme could be 

 invented satisfactory both to the emigrants and the 

 Colony. 



I ■— ♦-^— w^— 



Nitrogen Fixation in Tropical Soils. 



The need for further investigatiou into the 

 causes of variation in the rate of nitrogen fixation in 

 Indian soils is called attention to by Mr. C M. 

 Hutchinson, B.A., Imperial Agricultural Bacteriologist, 

 Pusa, in the Af/rwidtaral Journal of India. Vol. 

 XIV, Part 2. He says ^ ' Observat.ioiis made at Pu.sa 

 of the rate of fixations of nitrogen both in field soils 

 and in the laboratory, have confirmed my opinion thatJ 

 not only is the amount of nitrogen taken from the air 

 and added to the soil by azotobacter of considerable 

 economic importance, but that this amount may \ary 

 within such wide limits that it seems highly probable- 

 that, were we in posf ''ssion of more accurate informa- 

 tion as to the causes "f such variation, we should be 

 able to increase this amount very considerably, quite 

 possibly by mere soil management such as is made 

 use of to secure nitrification, or possibly the addition- 

 of some stimulating substance which ni.ay be ab.sent 

 in some soils ' 



One impt)rtant factor in the fi.xation of nitro- 

 gen in soils is probably the continuous and con- 

 current removal of the products of the bacterial 

 .action involved in the process of fixation. Another, is. 

 the provision of carbohydrates to supply the 

 bacteria with the necessary energy. But we nave only 

 to suppose a symbiotic relation.ship between azoto- 

 bacter, which is the chief nitrogen-fixing bacterium, 

 and crreen algae, to see how the process can proceed, 

 limited only by the necessary .soil moisture, and the 

 prose.ncc of such inorganic salts as are requisite for 

 the growth of these organism.s. 



The practical value of fully understanding the 

 process of nitrogen fixation is ileioonstrated by the 

 fact of its importance. In certain Punjab soils, 

 nitrogen fixation leads to the addition cf as much as. 

 ,30 per cent to the nitrogen content of the soil dur- 

 ing the year. 



