


66 THE NORTHERN MICROSCOPIST. 

reached us, and promises to be useful as a handbook to all those | 
studying or collecting our Fresh-water algae. It seems to be written 
on the lines of Rabenhorst’s “Flora Europea Algarum,” but 
though the classification is the same, the omission of Diatoms and 
Desmids, and the rearrangement of some of the genera, makes it” 
quite a distinct work. | 
Dr. Cooke starts off with the class CHLOROPHYLLOPHYCEA, © 
and in the order CoccopHYcE treats us to a minute description” 
of the Palmellacez, with which the whole of the twenty-eight 
pages is taken up. Perhaps the best feature of the work is that 
the plates are naturally coloured, and this generally goes much 
further in aiding the beginner than any written description, assisted 
by plain wood-cuts, could ever hope to do. % 
«There is an omission which, if noticed here, may perhaps be_ 
guarded against in future. The first genus Eremosphera is 
admirably illustrated by plate 1, containing 12 coloured figures, ~ 
but all the reference to it is “‘ Plate z, cells in various conditions, ~ 
all magnified 400 diameters ”—this is certainly too concise ; in a- 
work of this kind an explanation of each figure is very necessary. — 
Although, as we have already mentioned, the classification of” 
Rabenhorst has been followed, still his genera have been disturbed : 
our old friend Palmella cruenta, usually found as gelatinous blood-— 
like patches on moist walls or on the bare ground, and classified - 
by Rabenhorst amongst the RHopoPHYCEA, is here taken as the- 
seventh genus of the Palmellacez, and rightly, too, in our opinion, 
although we firmly believe that before many years are over, an_ 
entirely new and more rational system of classification will have to” 
be adopted, as it is by no means certain that the whole of the ~ 
order CoccopHycEe@, comprising the families of Palmellaceze, — 
Protococcaceze and Volvocinez, are autonomous members of the 
vegetable world. Palmella cruenta is here described as Porphy-— 
ridium cruentum, the only species of the genus. a 
Here we find also Palmella prodigiosa, the organism, generally — 
supposed a fungus, which forms blood-red spots upon cooked rice, 
bread, potatoes, etc. This protophyte has been a bone of conten-— 
tion between algologists and fungologists, and though it is here 
settled down amongst the algze, we cannot bring our minds to” 
consider the evidence brought forward in support of this view of a ~ 
definite or convincing character; but this, of course, is a matter 
of opinion. 
The plates are satisfactory, the printing also, and if the general _ 
character of the work is kept up, we have no hesitation in saying | 
that its issue will be a success. 3 q 
