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BRITISH BOG-MOSSES (SPHAGNACE.E). 
Bryoligists have already pronounced in favour of the very valu- 
able papers on Bog-Mosses, which Dr. Braithwaite communicated 
to the “ Monthly Microscopical Journal,” of which abstracts were 
republished in our pages. Since the period at which these were 
written, a collection of the specimens of Sphagnum therein des- 
cribed, has been published by the same gentleman, and we have the 
announcement of a complete monograph of the group, with intro- 
ductory chapters on the history and bibliography of the subject, 
which will render the Sphagnacce the most completely illustrated 
portion of British Bryology. Sufficient encouragement is only 
needed to induce its thoroughly competent author to advance still 
further, and perform similar good work on another group of our 
moss flora. 
In connection with this identical subject, it is our privilege to 
remind readers that an excellent series of microscopical prepara- 
tions have been made by the Rev. J. E Vize, of Forden, of Dr. 
Braithwaite’s series of Sphagnum specimens, mounted in his usual 
neat and artistic manner, which will be exceedingly valuable to all 
who possess the specimens themselves, and scarcely less valuable to 
those who do not, as illustrations of the cell structure of the leaves 
of the Bog-mosses. Bryologists now, as well as the students of 
other cryptogamia, cannot ignore the microscope, or refuse the 
assistance which the microscope affords in the determination of 
closely allied species. Those who are acquainted with Dr. Braith- 
waite’s papers need not to be reminded how much microscopical 
examination is needed for understanding properly and accurately 
the relations between the several species. It was, we believe, at 
the suggestion of Dr. Braithwaite, that the Rev. J. E. Vize was 
induced to prepare a limited number of sets of “ slides,” illustrat- 
ing the Sphagnacece, and as these are prepared from authentic 
specimens, they have an undoubted scientific value, apart from their 
value as interesting microscopic objects. We are informed that a 
very few sets of these unique preparations are still unsold, and may 
be had on application to the above-named gentleman, at Forden, 
in Montgomeryshire. The complete set costs about a guinea, and 
doubtless their value will increase rather than diminish with time, 
since all authentic preparations made carefully, and accurately 
named, will always possess a market value, which does not become 
attached to vaguely named, or fancy preparations, such as may be 
fashionable at public soirees one week, and condemned to oblivion 
the next. 
North American Algae. — We have just received intimation 
that the second Fasciculus of specimens, prepared by Messrs. 
Farlow, Anderson and Eaton, is published. 
