140 Miscellaneous. 
Jenner's and Ralfs’s drawings, but no one plate is a copy of any one 
of their published plates, although many of the figures contained on 
several are so, and this I conceive to be sufficiently acknowledged in 
the following quotation :—‘‘ Several of the figures of this family, 
especially certain of the genera Huastrum and Cosmarium, are taken 
from those of Jenner and Ralfs illustrating the series of papers om the 
Desmidie inserted in the ‘ Annals.’ ”’ 
The only instance in which there is any justice in the charge of 
non-acknowledgement is in reference to the genus Closterium, some 
figures of which genus are copied from Ehrenberg’s great work. 
This omission is however a mere oversight, and scarcely sufficient 
to support the grave charge of your reviewer. It is to be regretted 
that those of our botanists who haye paid attention to the genus did 
not send some specimens from which original figures might have been 
taken. ‘The blame as regards the drawings of this genus might be 
made to rest with more propriety upon others than upon myself. 
It can now be seen to what extent the following remarks of the 
reviewer are correct :— 
‘* It is unfortunate that the author has not pointed out the cases 
in which his figures are not the result of his own observations, but 
copied from published plates. 'The appearance of ‘ Hass. delt.’ at the 
bottom of ail the plates (the italics are my own) leads us to suppose 
that they are all of them original, but a more careful examination 
shows that not a few are copies.” 
In considering the charge of a want of originality in the * British 
Freshwater Algze,’ it should be recollected, that that work does not 
profess to be merely a summary of my own personal observations, 
but that it bears the title of a History, and as such it became the 
duty of the author to collect and insert all the information which it 
was possible to obtain in order that the subject might be rendered 
as complete.as it was in his power to make it. The introduction 
therefore of the five plates in question on points of such extreme im- 
portance and difficulty, and on which the author could not reason- 
ably be expected to furnish original drawings, should not be urged 
against the work as a fault, but should rather be allowed to speak in 
its favour. Their absence indeed might fairly have challenged re- 
proval. The charge of non-originality is one, whatever may be the 
faults of the work, from which I certainly expected to have been 
exempt, and one moreover which with the least show of justice can 
be maintained. 
On the subject of comparative characters the following obeeria- 
tion by your reviewer occurs :—‘“‘ The size of the filaments would 
doubtless be a valuable and most convenient mode of distinguishing 
the plants if it could be described in such a manner as to be always 
determinable, but comparative size can at no time be depended upon, 
unless the object with which the comparison is made be previously 
known.” ‘This statement of the reviewer is perfectly fair, and by 
means of an accurate micrometer, which instrument I did not pos- 
sess when I penned my descriptions, the relative sizes of the fila- 
ments of different species might have been satisfactorily. determined. 
