Moss — The Taxine in Irish Yew. 93 



Taxiue when precipitated from its solution in dilute acid is at first in a 

 state of extremely fine division. In a few minutes, if the quantity present is 

 not too small, the particles aggregate, and floeculent masses are formed, which 

 are very easily filtered and washed. In my experiments I washed this 

 precipitate on a weighed filter until tine washings, when acidulated with 

 nitric acid, gave either no turbidity, or only a faint turbidity with silver 

 nitrate. The precipitate was then dried in vacuo over sulphuric acid, until 

 the weight was constant. In this respect the method I employed differed 

 from that of Thorpe and Stubbs. 



A quantity of leaves taken on November 29th, 1908, from a female tree 

 growing at Ballybrack, County Dublin, weighed, in the fresh state and 

 detached from the twigs, 790 grammes. The leaves were dried at room- 

 temperature, powdered, and extracted as above. Tiie precipitate weighed 

 4-7093 grammes ; this corresponds to 0'596 per cent, of the original leaves. 



Thinking that more accurate results could be obtained with a much 

 smaller quantity of leaves, I gathered 150 grammes of leaves from the same 

 tree on January 11th, 1909; and taking every precaution to ensure complete 

 extraction, I obtained taxius weighing 0'9340 gramme, corresponding to 

 623 per cent. 



Seeds from the fruit of this tree treated in the same way, except that 

 they were ground to a fine pulp without drying, gave from 45-75 grammes 

 of seeds, taxiue weighing 0-0363 gramme, or 0-079 per cent. 



The leaves of another female tree gathered on December 6th gave taxiue 

 corresponding to 0-323 per cent. This tree had produced a very abundant 

 crop of berries. I found in the seeds 0-082 per cent, of taxiue — very nearly 

 the same proportion as in the other tree, while the leaves contained only 

 about half the quantity of taxine. The arillus or fleshy part of the berries is 

 quite free from taxine. I failed lo obtain any indication of tlie alkaloidal 

 substance, operating upon 300 grammes of the fleshy part. This is what one 

 might expect, consideriug the sweet taste of this part of the fruit, and the 

 complete absence of the bitter taste so characteristic of the leaves, bark, 

 and seeds. 



The residual pulp of the seeds, from which the taxiue had been extracted 

 by dilute sulphuric acid, was dried and extracted with ether in a Soxlet 

 extractor. On evaporating the ether a greenisli-coloured oil was left, corre- 

 sponding to 11-25 per cent, of the original seeds. This oil has a barely 

 perceptible bitter taste, probably due to a trace of taxiue. 



The leaves of a male specimen of common Yew growing in the same place, 

 but in a position much shaded in summer by large trees, gave a much smaller 

 quantity of taxine than the two specimens of Irish Yew. The precipitate 



