232 BOTANICAL GAZETTE [SEPTEMBER 
erous financial aid accorded by the Royal Society he has been enabled to pub- 
lish the full treatise at the Clarendon Press.?, Dr. Ewart’s observations upon 
protoplasmic streaming have extended over eight years. The treatise shows 
complete familiarity with the somewhat extensive literature bearing directly 
upon this topic, and the prolonged study has enabled him to review much allied 
work, both physical and physiological. In these days, when hasty publication 
is too frequent, the author’s mature consideration of his theme and the con- 
templation of it from many sides may be taken as an example worthy of imi- 
tation. 
Some conclusions of this book have already been stated in the notice of 
the preliminary paper. The study of streaming itself has brought Ewart to 
consider so many other aspects of cell physiology that it is not possible to 
summarize his conclusions without repeating the three or four pages in which 
he concisely does this. It must suffice to say that he discusses the influence 
of various external agents (including an extensive study of chemical, mechani- 
cal and etherial stimuli) on streaming; the relation between it and the other 
functions of the cell; the sources of energy; the influence of viscosity, and 
the ways in which this is modified by various agents; the analogies between 
streaming and molecular contraction ; the transmission of stimuli and the rate 
of propagation; the existence of nerve fibrillae as claimed by Nemec; the 
books of Sachs, DeBary, Pfeffer, and others, falling below their high standard 
only in the figures, which are reproduced from rather crude drawings. It 
would have been worth while to have a good draftsman put these into proper 
form. One dislikes to see unsightly illustrations in the midst of fine letter 
press.—C. R. B. 
Biological philosophy. 
SEEMINGLY almost all the fundamental problems of modern biology are 
at least touched upon in a curious work which has recently appeared from the 
hand of Krasan.4 The book is of a decidedly philosophical nature and is 
designed as a sort of introduction to broad and deep scientific thinking. [ts 
field is to some extent similar to that of Pearson’s Grammar of Science, but 
the present work deals almost entirely with the facts of botany, and the method 
of treatment as well as the ideas expressed are quite different from those of 
the Grammar. In KraSan’s felicitous illustrations and comparisons of things 
seemingly dissimilar (e. g., of the animate with the inanimate, etc.), is found 
2Ewart, ALFRED J., On the physics and physiology of protoplasmic stream- 
ing in plants. Imp. 8vo. pp. viii+131. fgs.77. Oxford: Clarendon Press. 1903- 
3See Bot. GAZ. 36:71. 1903. 
AN, F., Ansichten und Gesprache iiber die individuelle und specifische 
Rae in der Natur. 8vo. pp. vii+280. Leipzig: Wilhelm Engelmann. 1903- 
