to decide whether there was a diminution in the prophylatic 

 effect, and eventually the extent of this diminution. 



With a view to the importance of these investigations in 

 connections with the physiological test for rice which will 

 be given below, they are now given in detail, although 

 the final results have already been shortly indicated above. 



It is evident that the standard used by Fraser and 

 Stanton as to the proportion of phoshoric acid (at least 0.4%) 

 necessary for sufficient physiological working of rice, is of 

 no use in determining the effective properties. So long as 

 the active substances have not been separated and identi- 

 fied, physiological experiments alone can enlighten us as to 

 the extent of this working. 



Instead of taking comparatively expensive fowls and 

 pigeons wich had hitherto been exclusively and generally used 

 for animal experimentation in connection with beri-beri, reasons 

 of economy led to the trial of smaller birds for this purpose. 



For these experiments the rice-bird or glatik (Spermestes 

 orizyvora L.) turned out to be exceptionally suitable. While 

 house-sparrows (Fringilla domestica L.) scarcely lend them- 

 selves for these proofs, owing to the very slightly marked 

 symptoms of polyneuritis, the abovenamed rice-birds are more 

 suitable for test-animals than even fowls and pigeons. This fact 

 can also conduce to progress in the chemical investigation 

 of the effective substances contained in the silver-skin. 



The only advantage which house-sparrows have above 

 rice-birds is that when fed exclusively on completely polished 

 rice, they sooner become ill, frequently even in about ten 

 days. The picture of disease which they show how T ever is 

 not highly characteristic, and is limited principally to some 

 general symptoms, such as: gloominess, slow movements, 

 stooping carriage, ruffling of the smaller feathers, — while 

 symptoms of lameness (paralysis) were of very insubordinate 

 importance. 



With rice-birds on the contrary, which seldom became 

 ill within 3 weeks, it was just the paralytic symptoms which 



