86 
Review. 
advances that have been made and to obtain a general view of the 
whole body of our present knowledge. 
Professor Oltmanns’ bulky volume is the first (special) part 
only of his projected “ Handbuch,” of which he hopes to publish the 
second (general) part in the course of this spring. The present part 
of this extensive work will in itself, however, be of very great use 
to Algologists. Its full and clear treatment, with excellent and 
abundant illustration, of the very large amount of data now available, 
render it by far the most notable general work of reference on this 
fascinating group. At the same time it is full of interesting and 
suggestive discussions. As the author remarks in his preface, no 
general work has appeared since Falkenberg’s Algae was published 
in Sehenck’s “ Handbuch der Botanik ” (1882), and though the parts 
of Engler and Prantl’s “ Natiirliche Pflanzenfamilien ” dealing with 
the Algae by various writers, have helped to bridge this long interval, 
yet the form of treatment necessarily imposed upon contributors to 
that invaluable undertaking has prevented the work of Wille, 
Kjellman and Hauptfleisch on the green, brown and red algae 
respectively, from quite filling the place of a detailed handbook or 
treatise in which the author is free to devote any amount of space 
he may think desirable to general descriptions, comparisons and 
discussions. Furthermore our knowledge of the Algae has 
increased so enormously, even since the publication of the parts of 
the “ Pflanzenfamilien ” dealing with them, necessitating in some 
cases a revision of our fundamental conceptions of their morphology, 
that a fresh treatment is urgently required. 
A significant feature of the change which has occurred in the 
relative importance to be attached to the various groups in con¬ 
sidering the morphology of the whole is the large amount of space 
devoted at the outset to the plant-like Flagellata, and to the 
unicellular forms generally. “The Algae,” says Professor Oltmanns 
in his opening sentence, “go back phylogenetically to the Flagellata. 
That is a conviction which is continually making more headway . ..” 
And he goes on to point out that a recognition of this truth enables 
one to give a fixed position to many forms which have for decades 
been tossed backwards and forwards between Zoologists and Botanists. 
The work of Butschli, and particularly of Klebs, established this 
fundamental starting-point for a consideration of the morphology 
of the Algae beyond all doubt. Wille took up the main phylogenetic 
thread at the point where the algal characters become definitely 
predominant, and developed its ramifications with considerable 
