712 
Yew Poisonhtg. 
From the first two, and even from the last two, extracts these 
chemists obtained an alkaloid which seems to agree in most 
respects with the taxine of Lucas and Marme, although Amato 
and Caparelli do not give it this name, but call it nulossine. 
Lastly, and quite recently, Hilger and Brande have (in 1890) 
prepared a quantity of taxine by Marme’s process, using ether 
as the extracting menstruum. They employed yew leaves only. 
They give a more detailed description of the alkaloid than the 
previous writers, and claim to have prepai'ed one pure compound 
of it. For the alkaloid itself they suggest the complicated 
formula, C3»Hj20,oN (i.e. 37 combining weights of carbon, 52 
of hydrogen, and 10 of oxygen, to one of nitrogen). 
This brief sketch of what has been done only serves to show 
how little relevant to the current discussion, and how slight in 
itself, is our present knowledge of the yew alkaloid. We do 
not even know from which variety or sub-species of yew the 
supplies of material were obtained. There are at least three of 
these that merit separate treatment — common dioecious yew, the 
monoecious }’ew ' (with male and female iiowers on the same tree), 
and the Irish yew. The last named is reputed to be more 
poisonous than the common yew. Xo mention is made of 
whether the leaves were taken from a male or female tree in any 
case, though, as we have seen, one chemist examined the seeds 
as well as the leaves. The experimenters seem to have tried 
simply to confirm the report of yew being poisonous by proving 
it to contain an alkaloid of some kind, on which they are all 
agi'eed. Nearly all recorded work beyond this consists of purely 
chemical research in the direction of isolating, purifying, and 
studying the chemical compounds of the alkaloid found. 
The direct experimental evidence as to the poisonous action 
or precise therapeutic properties of taxine itself, or of extracts 
of yew leaves, is very meagre, d’aylor indeed, in his standard 
work on Toxicology, states that the poisonous nature of the 
alkaloid obtained by iMarme from yew berries (really, as we have 
seen, in greater quantities from the leaves') was experimentally 
determined by Borchers. So far 1 have been unable to obtain 
a copy of this work of Borchers — Exper. Untersxtch. H. Wirliung des 
Taxin: Gottingen, 1870 — and I can only hope that publication 
of the reference in this place will result in the unearthing of a 
‘ Montrredien, 2'reeii niid Shrubs for KutjUsh Planfaiions, p. 205, thus 
de.scribes it : — “ Taxus baccata Dorastoni, with horizontally spreading branches, 
which give it quite a distinct appearance. This variet}’ is inontECious. which 
character, if found to be constant, will entitle it to tlie dignity of a separate 
species.” Hooker believes “ the six supposed species of this genus to be forms 
of one.” 
