Review. 
32 
REVIEW. 
NOTES ON THE BLUE-GREEN ALG JE, WITH A KEY TO 
THE SPECIES OF OSCILLATORIA AND PHORMIDIUM. 
By Harold Wager, F.R.S. 
London (A. Brown & Sons), 1914, 48 pp., 2/6 net. 
T HE key, which is the most important part of this little book, is 
reprinted from The Naturalist for 1913. The idea is to provide 
a purely artificial key, in a readily accessible form, to the commoner 
species of these two genera, without relying primarily on the 
characters of the sheath. “ It is based mainly on the structure of 
the trichome as given in Gomont’s Monographic des Oscillarides,” 
and sheath characters are used only when there can be no doubt 
of their visibility. The diagnoses are not intended to be critical, and 
references are given to Gomont’s monograph, to Tilden’s “Minnesota 
Algae,” and to Forti in de Toni’s “ Sylloge Algarum ” for full diagnoses 
and figures. The key should certainly facilitate the identification 
of these rather difficult genera and is useful in bringing together 
the references to the monographs. There is a short introduction 
dealing with the general structure of the members of the group 
and a key to the orders and families, from which, however, the 
Glaucocystidece are omitted. A glossary is added : it seems slightly 
unnecessary, however, to explain such terms as chromatin, nucleus 
and epiphyte in a book of this type. The hook is well printed, 
excellent use being made of different types in the arrangement of the 
key. There are two slight misprints, “Tricohphoreae ” appearing 
for “ Trichophoreae,” and “ Chamaesiphoniaceae ” for “ Chamae- 
siphonaceae.” 
S.R.P. 
