PRESIDENTIAL ADDRESS SECTION B. 57 



quality and its low percentage of moisture, and because it is 

 carefully and impartially graded by the Government graders at 

 the ports of shipment."* And again with regard to fruit : " The 

 inspection of fruit at the Cape Town Docks has, however, done 

 a great deal of good, inasmuch as it has deterred shippers from 

 forwarding varieties unsuitable for this market, and fruit which 

 is badly packed or out of condition. "f If careful supervision 

 at the port of shipment has done so much to enhance our busi- 

 ness reputation as far as the fruit and maize trade are con- 

 cerned, it seems desirable to extend suc'n super\isi(jn to all other 

 exports. 



With regard to fodder plants, we depend largely upon the 

 somewhat unscientific and empirical method of leaving it to the 

 stock to determine what is wholesome and palatable in the way 

 of indigenous plants. There are hundreds of wild-growing 

 species of which we know very little more than their distribution 

 and habitat. Of only a small portion do we know the nutritious 

 value, and one would imagine that such knowledge wcjuld be of 

 the utmost benefit to stock- farmers, particularly in the ari.l 

 Karroo region, where stock is entirely dependent for its subsis- 

 tence on these wild shrubs. The whole question of the food 

 value of indigenous shrubs, the distinction between edible and 

 poisonous species of the same genus {Euphorbia), the tem- 

 porary protection and systematic cultivation, is so important that 

 the suggestion has been put forward to establish an experi- 

 ment station in the Karroo for the purpose. | The changes pro- 

 duced in fodder ])lants bv drought, w'ilting and withering, have 

 hitherto not received the attention they merit. Cyanogenesis in 

 many well-known stock foods under certain climatic and telluric 

 conditions is a well-known phenomenon, and has been observed 

 in Kaffir corn, beans and linseed, and fatal effects have also 

 been traced to the accumulation of potassium nitrate during 

 rainless periods in stunted and partly withered Kaffir corn. 

 Might not some of these observations in the case of well-known 

 fodder materials be a clue as to wdiere to look in the case of some 

 of the mysterious and unaccountable stock diseases. If it is 

 not prussic acid, it may be some other |X)ison developed under 

 conditions of drought. But mere speculation is valueless. Ex- 

 perimental data are required. 



The suggestions which I have put forward for organising 

 phytochemical research may be briefly put as follows : — 



( I ) The formation ()f a small Committee for the purpose 

 of distributing the work, co-ordinating the results of different 

 collaborators, of arranging for joint publications, etc. 



(2) The establishment of a central reference library with 

 a staff of student abstractors, and, as a temporary measure, the 



* Loc. fit., p. 24. 

 t Loc. cit., p. 54. 



jR. Marloth : Prosidontial Addnss to tlic S.A.A.A.S., Kimberlev, 19T4. 

 p. 8. 



