SECTIONAL TRANSACTIONS.— I. 397 



constant current. The ascent of sap is not wholly a physical but fundamentally a 

 physiological process, not essentially different from the mechanism of propulsion of 

 blood in the animal. The parallelism extends to such points as the necessity of an 

 internal hydrostatic pressure to evoke the rhythmic contraction, the association of 

 electrical with mechanical changes, and the stimulant or depressant action of sub- 

 stances which have these effects on the animal heart. 



The results prove that in these three striking reactions, the mechanism of life of 

 the plant is essentially similar to that of the animal. The simpler type of plant 

 organisation offers experimental advantages, and such experiments may well lead to 

 the solution of perplexing problems. 



8. Discussion on The Relationship of Vitamin B to ' Bios.' 



(a) Prof. R. A. Peters. 



Since, at the beginning of the present century, Wildiers, in the laboratory of 

 Professor Ide, put forward the view that yeast needs, for rapid growth, traces of some 

 unknown organic constituent, 'bios,' there has been much work and considerable 

 dispute on this topic. It has been shown by G. L. Peskett that, while Medium F. 

 (Fulmer, Nelson and Sherwood) does not grow all yeasts efficiently, the addition to 

 this medium of small amounts of anti-neuritic concentrate induces enormous 

 acceleration of the multiplication. Such a ' stimulant ' effect can bo obtained from 

 the preparation even after inactivation, by alkali, of its anti-neuritic properties. 

 Such anti-neuritic concentrates therefore show ' bios ' activity, but the reverse is 

 not true. 



(6) Mr. 6. L. Peskett. 



(c) Miss Reader. 



A basal synthetic medium for the cultivation of Sirepiothrix corallinus was 

 devised. To this additions of anti-neuritic concentrate (Kinnersley and Peters) were 

 made. As little as 1/40,000 of a ' pigeon-dose ' in 20 ccs. of the synthetic medium 

 stimulated growth, while when greater doses were used the organisms were of 

 abnormally large size. 



Parallel tests, during fractionation of brewers' and of bakers' j'east, show that 

 anti-neuritic power (pigeons) and growth-producing power (Sirepiothrix corallinus) 

 run parallel as far as a concentrate of which 0-2 mgm. contains one ' pigeon-dose.' 

 Both ' factors ' are inactivated by alkali ; indeed, the growth-producing factor for 

 S. corallinus may be identical with the anti-neuritic factor. 



{d) Miss Orr-Ewing. 



The addition, to nutrient agar medium, of anti-neuritic concentrates did not 

 induce the growth of either Meningococcus, Gonococcus, or Bacillus Influenzae. 

 Meningococcus will grow on charcoal-extracted meat-extract medium containing 

 no vitamin (pigeon test) and no growth-producing factor for Streptothrix corallinus. 

 The Meningococcus, therefore, does not need anti-neuritic vitamin for growth. By 

 a process of exclusion, it is concluded that the gonococcus-growth-promoting factor 

 present in blood and other fluids is not anti-neuritic vitamin. 



9. Prof. J. C. Drummond. — Observations on the role of Vitamin B 



in Animal Nutrition. 



Monday, August 9. 



10. Discussion on Reflex Posture. 



(a) Dr. F. M. R. Walshe. 

 (6) Prof. J. A. GuNN. 



(c) Prof. Sir Chas. S. Sherrington, O.M., G.B.E., F.R.S. 



(d) Mr. D. Denny-Brown. 



