136 BOTANICAL INFORMATION, 
from tropical Africa. Aciphylla squarrosa and 4 Stenopetala,* 
Rhodoplexia Preissii, Harv. Several Ferns, recently described 
in the “Species Filicum:” Pholisma arenarium, Nutt. ; two 
Gentians from New Zealand, Cabomba Piauhiensis, Gardn., 
and Caroliniana; Apodanthes Calliandre, Gardn. (N. O. 
Rafflesiacee) ; Schiedea Nuttallii, &c. 
A History of the Birrisu FRESH-WATER ALGÆ, by ARTHUR 
Hinr HassALL, Surgeon. 
Mr. Hassall is well known for his researches among the 
fresh-water Alge, and we rejoice to find that he has prepared 
materials for a work on these beautiful objects, which cannot 
fail to be acceptable to the lover of Cryptogamic Botany, 
and indeed to all who take an interest in the works of nature. 
We have seen a large proportion of the drawings, and we do 
not hesitate to say that they are eminently adapted to illus- 
trate, in the most satisfactory manner, the structure and 
mode of reproduction of these curious aquatics. The work 
will very shortly appear in one volume octavo, with seventy 
plates, executed in lithography by the author, representing 
the magnified appearance of every species of the orders of 
Confervacee and Diatomacee, hitherto discovered inhabiting 
the soft waters of the British Isles. It will contain, in about 
three hundred pages of letter-press, a complete account of 
the modes of reproduction, growth, vitality, distribution, 
uses, classification and species of this extensive and interest- 
ing group of plants; interesting from the importance and. 
number of the physiological and anatomical facts connected 
with their history. Notless than four-fifths of the species 
to be here described, are considered by the author as either 
new or such as have not been described in any systematic 
work on the Alge hitherto published; this considerable in- 
* One ‘of these, the S. draboides, Tab. 617, seems to be the Menkea - 
australis, briefly characterized by Lehmann, in his Catal. Semin. of the 
present year, and raised from seeds sent by Mr. Preiss from the Swan river 
settlement. 
