1469 
in special unknown accessory food-stuffs, which Funk’) has included 
under the general name of vitamins, while the diseases themselves 
are classed as “deficiency diseases’ or ‘“avitaminoses’’. 
The foundations on which the deficiency-hypothesis has been built 
were furnished by. the evidence of my own experiments, showing 
that not only rice-polishings of themselves, but also an extract from 
them, possesses prophylactic and remedial properties against polyneu- 
ritis gallinarum,*) and showing also that neither deficiency of protein, 
nor of fat, or salt produced the disease*). This, however, did not 
eject the poison-hypothesis, which, after all on the basis of the 
facts had also to assume a deficiency in the diet, notably a diet 
defective in a substance (or substances) that rendered a poison 
innocuous or prevented its formation. Considering the poison- 
hypothesis to be merely a basis for further researches [| suggested 
in my earlier publications ®) three possibilities, viz. a poison ingested 
with the food, or a poison evolved from the food in the alimentary 
canal (through the agency of micro-organisms >), or a poison produced 
by a disturbed metabolism in the tissues. Elsewhere*) I have 
demonstrated elaborately why the first possibility may be rejected as 
clashing with indubitable facts, and also that though the second and 
the third could not be excluded, positive evidence could not be 
adduced. It is the analogy to the neuritis, incited by common poisons, 
such as lead, arsenic, alcohol, ergot and some bacterial toxins, 
that proves for an intoxication; however the question could not be 
settled as in spite of numerous attempts no one has succeeded 
as yet in assigning a poison as the etiological factor of polyneuritis 
gallinarum: 
The following may serve to illustrate how interpretations of 
experimental data, obtained in this field, vary with the view-point 
of the experimenter. 
Funk %) and likewise Brappon and Cooper °) believing the 
deticieney-hy pothesis to be correct, arrive at the conclusion that it 
is especially the carbohydrate metabolism that causes a more 
abundant consumption of antineuritic matter. By increasing the 
content of carbohydrate in a mixed diet, they succeeded in hastening 
1) Journ. of State Medecine, Vol. 20, p. 341, 1912. 
2) Arch. f. Hygiene, Bnd. 58, S. 150, 1906. 
3) Gen. Tijdschr. v. Ned. Indié, Vol. 36, p. 213, 1896. Virchow’s Archiv, 
Bd. 148, S. 523, 1897. 
4) XVIIth Intern. Congress of Med. London 1913, section XXI. 
5) Horre Seyter’s Z. f. physiol. Chemie, Bnd. 89, 5. 378, 1914. 
6) Journ. o. Hyg. Vol. 14, p. 331, 1914, 
