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 Euastrum and Cosmarium, are taken 

 from those of Jenner and Ralfs illustrating the series of papers on the 

 f)£smidice inserted in the * Annals.' " 



^^j -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 have 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 



l^yiewer are correct : — 



As^ '* ^^ ^^ unfortunate that the author has not pointed out the cases 

 lit 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 all 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 Algae,' 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 observa- 

 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. 



