308 TRANSACTIONS AND PROCEEDINGS OF THE [Szss. uxxn. 
not poisonous, but when injected into the blood is one of the 
most powerful poisons known, one-sixty-fourth of a grain 
being sufficient to kill a man. 
On behalf of Mr. PETER FENTON, the President exhibited 
the fruit of Pithecoctenium echinatum and the seed of Mucuna 
urens from St. Helena, the seed of Entada scandens from 
India, and Bertholletia excelsa from South America. The 
Pithecoctenium was described as a new species which does not 
appear in the “ Index Kewensis.” It was first deseribed by 
Karl Schumann. 
In Professor Bayley Balfour’s absence Mr. H. F. Tace, 
F.LS., exhibited a portrait of Mr. Wm. M‘Nab, at one time 
chief of the gardening staff of the Royal Botanic Garden, 
and an original Fellow of the Society. The portrait, prepared 
from a calotype in the possession of Miss M ‘Nab, a grand-~ 
daughter of Mr. M‘Nab, will appear, with an account of Mr. 
M‘Nab’s life, in “ Notes from the Royal Botanic Garden.” 
Dr. A. W. BorTHwick showed specimens of a gooseberry 
shoot disease, caused by Coniothyrium sp. 
Mr. Harry F. Tace, F.LS., exhibited a specimen of a 
gooseberry bush which had been killed by the attack of a 
root fungus, Agaricus melleus, Vahl. 
The specimen, the exhibitor explained, wus one of several 
secured during a visit to Kent, where of recent years the 
losses to growers occasioned by the ravages of this parasite 
have assumed considerable proportions. In the plantation 
irom which the specimen was taken large patches of goose- 
berry bushes attacked by the fungus were observed, and it 
was estimated in this one plantation alone over a thousand 
plants were affected. ; 
It was pointed out that when once the mycelium of the 
fungus had established itself in the roots and stool of a tree, 
nothing could be done to save it, and plants so affected ought 
certainly to be destroyed. 
The difficulties of combating fungal diseases of this kind, 
where the mycelium of the parasite is able to spread from 
tree to tree through the soil, and the necessity of taking 
