1914] The Cambridge British Flora. (Review) 199 
well. In presswork, paper and binding the book is dignified and sump- 
tuous, as would be expected from the Cambridge University Press. 
In arrangement the work comes to date and, the Introduction tells us, 
is the first British flora based upon the system of Engler & Prantl. 
In nomenclature the international rules adopted at Vienna and Brus- 
sels are followed as are the international recommendations of groups 
to be recognized (species, variety, forma, etc.); but with occasional 
intentional departures from the nomenclatorial rules and recommenda- 
tions such as many authors feel it incumbent upon themselves to make, 
although by so doing they defer the day of stability in our nomenclature. 
The text is very full and is accompanied by text-maps showing the 
distribution of each species in the British Isles, and each accepted 
species is illustrated by a full-page line-drawing plate. When com- 
pared with the excellence of the text, the plates are disappointing for, 
although faithful in outlines, they fail to catch much of the " gesture" 
of the plant, and in many cases they do not bring out clearly the tech- 
nical diagnostic characters which a critical student is anxious to see. 
It is furthermore probable that the desired contrasts would be better 
emphasized if some of the closely related species could be illustrated 
on one plate; and at the same time, the plates would, in many cases, 
give less the impression of occupying needless space. For instance, 
everyone who has studied intensively our annual species of Salicornia is 
interested in Dr. Moss’s attempts to segregate them and would be 
greatly aided in understanding the proposed species if diagnostic fig- 
ures could be seen side-by-side; but in the Cambridge British Flora 
each species, however small the plant, is given a full plate, with the 
result that 100 sq. dm. of plate-paper are used to bring out the figures 
(not entirely convincing) of the annual species of Salicornia, which in 
the aggregate occupy only 25 sq. dm. of space. 
In the recognition of species the Introduction states that “a middle 
course is desirable.” Probably all of us, however radical, will readily 
subscribe to this ideal; the difficulty is clearly to see and to follow the 
“ middle course." In many of the technical groups — the Salicaceae, 
Betulaceae and Polygonaceae, for example — the treatments are ob- 
viously guided by this precept and systematists throughout the north- 
ern hemisphere will find much in the elaboration of these families that 
will be directly serviceable or at least suggestive in the working out of 
their own local problems. But it will require a much-altered concep- 
tion of specific values to accept without question all the "species" 
recognized in the Atriplex patula series or in Salicornia. For example, 
it is not clear to the uninitiated that in Salicornia such diagnostic 
statements as the following are indicative of distinct species:— 
*5. S. pusilla (p. 193). Stem erect, up to about 1'0 to 1'5 dm. high, 
branches curved-ascending. Terminal spikes short, up to about 5-12 mm. long, 
with about 2-4 flowering segments. Lateral flowers smaller than the central 
one. Stamens 1. 
