25 
On the Fruits and Seeds of Rhamnus . 
We have now to enquire as to the biological significance 
of these matters. I have germinated the seeds of Rhamnus 
infectorius once or twice, but have frequently failed to make 
the seedlings grow at all. 
So far it has been only from whole fruits that seedlings 
were obtained : all the specimens of shelled naked seeds 
have failed. In the successful cases the pericarps swell, and 
become yellow and slimy, the soil around being dyed with the 
colouring matter, and fungi seem particularly apt to appear 
on the rotting pericarps. It seems an obvious suggestion that 
this is due to the glucose. But it is also a suggestion worth 
further investigation that the glucose is of use to the young 
embryo, and I am strongly inclined to the belief that this is 
the case, and that the cause of failure with naked seeds lies 
partly in this. At the same time the matter needs further 
investigation. 
Another point is — do birds or other animals eat the fruits ? 
I find them distinctly bitter and resinous to the taste at first, 
and they are known to be purgative. It seems not unlikely 
then that they are not eaten by animals, though they may be 
carried and broken by them. 
My idea that the glucoside stored in the pericarp is for the 
benefit of the young plant is not without support from analogy, 
and it is well known that the amygdalin of bitter almonds is 
contained in certain cells of the seed, the ferment (emulsin) in 
other cells : so also with mustard seeds — the ferment (myrosin) 
which breaks up potassium myronate into glucose and other 
bodies exists apart in the seed. 
It is, however, a peculiarity that in this case the glucoside 
should be in the pericarp and the ferment in the raphe of the 
seed, a phenomenon which is again suggestive in view of our 
growing conviction that many glucosides, hitherto regarded as 
more or less waste products, are really not excluded from the 
constructive metabolism of the plant. 
