ELECTRICAL PHENOMENA AND METABOLISM OF ARUM SPADICES. 469 



comparable with trypsin in attacking proteids and peptones, but carrying 

 the process of splitting to a further stage in which tryptophane can no 

 longer be detected. 



The proteids used were : The tissues of the plant itself (H. P. K. 

 and M. T. F ) ; Vermicelli (M. T. F.) ; Fibrin (H. P. K. and M. T. E.) ; 

 Barley (H. P. K.). 



The enzymes will not attach themselves to the solid proteid par- 

 ticles, but remain in the solution (fibrin standing for some hours in 

 spadix extract and then washed remains unattacked. — H. P. K. and 

 M. T. F.). The use of a bottle- shaker, therefore, greatly accelerates the 

 action. 



Miss Fraser has succeeded in showing the complete destruction of 

 tryptophane (in a pancreas digest) by the addition of spadix enzyme, the 

 boiled control giving at the same time a strong tryptophane reaction. 

 This point, which seemed so probable last year, it was chiefly desired to 

 establish. 



Miss Fraser is still experimenting as to the splitting of sugars by 

 the plant enzymes. It may be remembered that the splitting of starch 

 was shown by all species investigated : but the fact that we could not 

 ascertain which sugars resulted by any of the ordinary methods has sug- 

 gested this possible further stage on the carbohydrate side parallel to the 

 complete breaking down of the proteids. 



{b) Nuclear Conditions. — The first point which attracted me to the 

 investigation of the aroid inflorescence was the idea that they would 

 probably show nuclear changes governing enzyme secretion similar to 

 those which Miss Huie found to exist in Drosera. I have fixed material 

 in some of the media advocated by Dr. Gustav Mann at different stages : 

 bud, hot-phase, fading-flower. 



Paraffin sections stained by Mann's metbyl-blue-eosin method, or in 

 haematozylin-eosin, display a short mitotic phase (from generally dis- 

 tributed chromatin to chromosomes) accompanied by an inversion of ionic 

 conditions in A. dracuncidus. 



Notes hy Miss Fraser, B.Sc. 



I. Auto-digestion. — Extract of spadix of Amm dracunculus shows tryptophane, 

 which disappears after twelve hours— boiled control negative. 



Extract of spadix of Aram italicum gives starch disappearance in twelve hours 

 in unboiled solution after several days in boiled control. 



Tryptophane never appears in extracts of stem and leaves. 



II. Mixtxires of Extracts of Spadices with various Substrates. — Extract of spadix 

 of Arum crinitum with tryptophane solution gives disappearance of tryptophane 

 after four days in unboiled solution. Tryptophame still present in boiled after 

 fourteen days. 



Spadix of Arum dioscoridis spectahile after ten days gives disappearance of 

 tryptophane in unboiled extract. 



Extract of spadix of Arum dioscoridis spectabile with vermicelli gives trypto- 

 phane after a week — boiled control negative. 



Extract of spadix of Arum dracunculus with Witte's peptone gives tryptophane 

 after a week — boiled control negative. 



Extract of spadix of Arum dracunculus with fibrin gives tryptophane after 

 ten days. 



Extracts with casein, gelatine, give negative results. Extracts of spadices of 

 Aurum crinitum, dracunculus, dioscoridis spectabile give no disappearance of sugar 

 after ten days in solutions of dextrose and maltose (5, 3, 2, and 0'.5 per cent.), but 

 those experiments are still in progress. 



