NEW PUBLICATIONS. 219 
absent from this Flora. It is to be regretted that the illustrations of 
the genera, which so much enhance the first part of the volume, are 
not extended to the Mosses and Hepatice. Their want is the more 
to be wondered at as they are promised for the Lichens and Fungi. 
The value to the beginner of such accurate and inexpensive woodcuts 
as those of Dr. Rabenhorst’s cannot be over-estimated. It has sur- 
prised us that they have not been more extensively used. The only 
work published in this country with ‘such illustrations, as far as we 
know, is Mr. Gosse’s work on marine zoology, in which, for a small 
sum, an accurate drawing of every genus of vertebrate and inverte- 
brate animals inhabiting our seas is given. Why could not this be 
done more for botanists? We want a work on British Cryptogamia. 
It is thirty years since the fifth volume of the ‘ English Flora’ appeared. 
In the interval there have been published monographs of the different 
Orders by Berkeley, Wilson, Smith, Harvey, Mudd, ete. These form 
a somewhat large and certainly an expensive library, beyond the reach 
of most botanists. A new edition of the now scarce Cryptogamic vo- 
lume of the ‘ English Flora’ would be a great boon to workers, for the 
interval of thirty years makes it to a considerable extent useless to its 
fortunate possessors. Great accessions to species have specially been 
made in the minuter organisms. Thus, the 2 species of Desmidee have 
increased to 182, and the 54 Diatomacee to more than 700. 
The eminent position Dr. Rabenhorst has attained as a careful and 
critical observer by his former works, as well as by his published fasci- 
culi of plants, is strengthened by this useful Flora. We conclude by 
quoting from the preface some instructive sentences on the disappear- 
ance of habitats of Algz and Chare, plants the appearances of which 
depend upon manifold, but little-known influences. ‘ We know, in ge- 
neral,” he says, “ that continued rain, and a higher level of the water m 
rivers, lakes, and morasses than usual, are as injurious as à great 
drought. In the years 1855, 1857, and especially 1858, many species 
were altogether wanting in localities where they were formerly well 
nown. In 1858, the Chare were everywhere sought for in vain. 
Chara glomerata, C. polyacantha, and Nitella syncarpa have disappeared 
within the last few years, and N. mucronata since 1855 ; it will be of 
great interest to observe the time and circumstances under which they 
reappear. In 1857, Hydrodictyon appeared in some places in such 
quantity that ponds and reservoirs were almost filled with it; since 
