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will lie on a sheet of this size and leave considerable room between. I begin 
by placing two pockets side by side at the bottom of the page and stretching 
a strip one inch wide of the same stiff paper as the sheet itself across the 
page high enough up to let the flap of pocket fold over it at the joint or 
crease. This strap is held in place by half inch strips of commercial 
gummed paper at each end and one in the middle. This- is repeated until 
all the eight pockets are in place, and then you have a sheet which can be 
handled as carelessly as you please without disordering your specimens in 
the least; while on opening the sheet you can see at a glance what it con- 
tains, select your pocket and remove it with perfect ease. On the lower left 
hand corner outside of the sheet can be inscribed the name of the genus 
which it contains, or the letter with which several genera enclosed begins 
and the sheets placed in alphabetical order. 
I have as yet only about one hundred and fifty species, but should 
arrange them the same if I had one or two thousand species. The facility 
of reference more than makes up for lack of scientific arrangement which 
must lie in one’s head rather than in the sheets. Of course the Hypneae are 
kept in a cover b}^ themselves and their different genera or subgenera 
arranged in similar alphabetical order. 
Several genera of mosses like Antitrichia, Fontinalis, Hylocomium, 
Neckera, Sphagnum and the others require pockets of double size. Four of 
these will go on a page if slipped under the straps endwise without refer- 
ence to the flaps. I find that an average of ten to twenty sheets containing 
both small and large size pockets will hold about six pockets to the sheet. 
Consequently it will be seen that it takes comparatively few sheets to hold 
quite a respectable collection of mosses, especially as two or three duplicate 
pockets of the same species can be slipped into one loop together. The 
trouble of mounting is very small while the ease of handling and selecting 
is very great. Clayville, New York. 
MUSCI BOREALI-AMER1CANI BY PROF. J. M. HOLZINGER. 
A. J. Grout. 
Fascicles II and III of Prof. Holzinger’s Musci Acrocarpi Boreali-Ameri- 
cani were issued in rapid succession ; both contain numerous interesting 
species. Fascicle II contains among other interesting species: Poly- 
trichujn Smithiae Grout, Anomobryum filiforme Americanum R. & C. r 
Fissidens decipiens Winonensis R. & C., Coscinodon Raui (Aust. ) L. & J. r 
C. Wrightii (Aust.) Sull., Bryum Duvalii lato-decurrens C. M. & Kindb., 
B. Sawyeri R. & C., Catherinea mollis Holzinger and Dicranum fragili- 
folium Lindb. Fascicle III contains the following: Syrrhopodon Flori- 
danus Sull., Orthotrichum cupulatum Por teri Vent., Schistidium aipicola 
rivulare (Brid.) Wahlenb., Tetraplodon Australis Sull. & Lesq., Barbula 
Raui Aust., Amphidium Mougeotii (B. & S.) W. P. Sch. and Bruchia curvi- 
seta L. & C. - 
No student of North American mosses should feel satisfied without Prof. 
Holzinger's exsiccati. 
