70 
The Presidenfs Address. 
and the affection yielding to the administration of the alum, 
the plant should find its way to the opposite organ without 
any perceptible path ; but if it were not actually observed in 
at least an early stage of development^ it does not appear 
by any means certain that it would have been found at 
all, because^ so far as I am enabled to judge, and from the 
all but universal testimony of those who have had opportu- 
nities of observation combined with the necessary capacity 
for coming to a sound conclusion,, the parasitic fungoid growth 
should be regarded rather as the consequence than as the 
cause of organic disintegration. 
I think it but right to observe that Mr. Grove does not 
express an opinion either way. 
The four papers relative to botanical science are all of 
them connected with the Diatomacese, the especial pet subject 
of microscopists — a fact by no means surprising to those who 
have gloated over the elegance and variety of form and 
structure displayed by the gem- like remains of these minute 
members of the vegetable kingdom, especially as from their 
permanent character they are not liable to suffer from the 
destructive hand of time. The papers are, firstly, " On a 
Diatomaceous Deposit in Leven Water, near Coniston," by 
Amos Beardsley, F.L.S., &c., and On the Menai Straits as a 
locality for collecting Diatomacese,^^ by B. J. Nowell. These 
do not pretend to do more than direct attention to the favor- 
able nature of the localities quoted for collecting specimens, as 
producing abundantly a considerable variety of forms, each 
paper being furnished with a short list of some of the species 
noted. Secondly, two papers, by Dr. Donkin, of Morpeth — 
one On a species of Filamentous Diatom new to Britain 
and another, " On the Marine Diatomacese of Northumber- 
land.^^ The species of filamentous diatom alluded to is the 
Sydendrium diadema of Ehrenberg, hitherto only noticed as 
a fossil production, or found amongst the Peruvian guano. 
There appears to be a difference of opinion amongst the 
authorities" as to the right of this genus to rank in the order 
of Diatomacese, the late Professor Smith and others having 
declined to recognise it as such, whilst many others have 
admitted the claim ; but which ever way the controversy may 
be decided, the fact of its habitat as indigenous to our own 
shores becomes established. 
Dr. Donkin^s second paper contains a description of a 
mode of collecting Diatomacese on the sea- shore, that is well 
worthy of imitation, and I would recommend those who 
may be intending to collect in similar localities to read care- 
fully the description given in pages 14 and 15 of the present 
