— 4 — 
is to be congratulated on the accuracy of her drawings and the rapidity with 
which she does them. We hope that this maiden task in hyper-critical study 
will not discourage her from undertaking furtheF^work in Bryology.^ She has 
been devoting her major energies to Bacteriology for the Red Cross, and it is 
understood is contemplating devoting herself to this work as a profession. 
New York Botanical Garden. Elizabeth G. Britton. 
A. Hesselbo — The Bryophyta of Iceland 1 
This is decidedly one of the most important bryological works of recent 
years, as Iceland was, in respect to its bryophyte flora, the most neglected of 
fairly accessible northern lands. Lists prior to those of Gronlund the present 
author finds to be essentially worthless, while those of Gronlund himself were, 
besides being incomplete, rather faulty. The present author’s collections and 
observations were made upon three summer trips, in 1909, 1912 and 1914, and 
the greatest weakness of the work lies in the fact that the whole island could 
not possibly be covered by such limited field work, as the author realizes. Still 
one is impressed by the remarkably good use made of the time at his disposal. 
There are listed 93 hepatics, 20 Sphagna , and 324 (or including 2 subspecies, 326) 
true mosses. The attention paid to species found only in sterile condition 
shows the carefulness with which the author worked. Old records which were 
based upon wrong identifications or are otherwise suspicious are not included, 
though notes upon them are inserted. The flora of Iceland is, as has long been 
known, essentially northern European, among the mosses Bryoxiphium norvegi- 
cum being a unique case of a species found in Iceland and North America, but 
lacking in Europe. Two new species in Bryum and one in Brachythecium are 
proposed. Under the separate species are remarkably detailed notes as to 
habitat, while the whole is summed up in an oecological supplement. Most 
interesting in this is the careful study of the flora of the various hot springs. 
Species of Riccia, Anthoceros, Archidium, Enloslhodon, etc., were found confined 
to warm ground of this description, while other bryophytes found their best 
development and most frequent occurrence under such conditions. One thing 
missed in this part of the work is an adequate discussion of geological substrata, 
particularly as to their chemical constituents. It is for example certainly to 
be expected that the flora of the areas of acidic lava would differ from that of 
basic lavas, and there is even a limited area of sedimentary rock (apparently 
visited by the author near Husavik). A good geological map, by Thoroddsen, 
makes it possible to lay out one’s route somewhat with reference to these differ- 
ences and to at least gain some fundamental ideas of the effect of the different 
rocks upon the moss-flora, which a work on the comprehensive plan of this one 
demands. Of the additions which I have published, 2 all with two exceptions, 
Pleuridium alternifolium and Dicranella Grevilleana, are included on the basis 
1 Rosenvinge & Warming. The Botany of Iceland, Vol. I, Part 4. Pp. 395-677. 1918. 
? Bryologist 18 : 5if. 1915; Torreya 16 : 47ft. 1916; 17 ; 6off. 1917. 
