412 Bibliographical Notices. 
The figure of Botrydium granulatum is evidently a reversed copy of 
part of Dillwyn’s plate of Conferva multicapsularis, and yet Mr. Hassall 
quotes that synonym doubtfully ; thus allowing that, even in his own 
opinion, his figure may not represent B. granulatum. Why not state 
this ; and also why not copy Greville’s figure, which certainly repre- 
sents the true plant ? 
We now come to the Desmidee, to our mind the least satisfac- 
tory part of the book, for we suspect that here the author is far 
less at home than in the preceding families. A more prominent 
reference might have been made to the very successful labours of 
Mr. Ralfs upon this family, and also the Diatomacee, which have ap- 
peared in our pages, and are now published in a collected form in the 
‘ Transactions’ of the Edinburgh Botanical Society. From these 
papers Mr. Hassall has avowedly transcribed the remarks on several 
of the species, and has apparently copied by far the greater number 
of the figures of the Desmidee. He does state that “several of the 
figures of this family, especially those of the genera Huastrum and 
Cosmarium”’ are so obtained, but might have added, that nearly if not 
quite every figure of Staurastrum, Scenedesmus, Pediastrum, Xanthi- 
dium and Tetmemorus have the same origin. We do not blame him 
for copying these beautiful drawings, but he ought to have taken 
better copies, and also acknowledged his obligation to their author. 
Nearly all the figures of Closterium we think are derived from Ehren- 
berg ; the figure named CZ. Junula is not that species, but a variety of 
Cl. Khrenbergi. In this case an acknowledgement was the more 
necessary, since it is more than probable that some of the figures do 
not represent British species; for instance, our Cl. margaritaceum 
differs from Ehrenberg’s figure in not being granulated, and is 
perhaps distinct ; Ehrenberg’s Cl. digitus is not the same as the spe- 
cies so called in Britain. 
We cannot however afford time or space to hunt out and record 
all these errors, nor indeed the very many erroneous references to 
synonyms, but merely observe that Mr. Ralfs is frequently made to 
have used a nomenclature quite different from that which really 
exists in the ‘ Annals’ and ‘ Transactions’ ; and that the references 
to Mr. Jenner’s ‘ Flora of Tunbridge Wells’ are incorrect in nume- 
rous cases. This is really too bad, as a very little ordinary care would 
have prevented it. We readily forgive an author for mistakes, for to 
them we are all liable; but carelessness of this kind and to this ex- 
tent is unpardonable. 
Mr. Hassall justly remarks, that our knowledge of these plants is 
far from being complete. We believe that the number of Closteria is 
much greater than is supposed by him, and know of many additional 
species in some of the other genera. 
In the present infancy of our knowledge, much difference of opi- 
nion may exist as to the characters which should constitute genera ; 
many may agree with Mr. Hassall in considering Desmidium, for ex- 
ample, to have been too much dismembered by previous writers ; and 
some will probably think that he has himself introduced unnecessary 
divisions, as for example, Arthronema (p. 238) and Hassallia, origi- 
