CURRENT LITERATURE. 
‘ BOOK REVIEWS. 
Experimental morphology.* 
It is with pleasure that we welcome a text-book in this comparatively 
new field of biology. While embryology is investigating the problem, ow 
adult forms are produced, it is the new school of physiological morphology 
that deals with the question “wy does an organism develop as it does?” 
And it is with this question of such great importance to physiologists and 
morphologists alike that this work occupies itself. 
S This first part is devoted to those processes which are characteristic of 
« all living protoplasm, and it is quite needless to say that both plants and ani- 
pe mals are included in its range. 
One of the characteristics of the book is the stress laid upon quantitative 
measurements of agents and effects. No better opening sentences could 
have been selected than those of Jaeger and Jevon: 
morpholugische Betrachtung setzt also eine genaue chemische und physika- 
lische PTT 1. des betreffenden Korper selbst und 2. aller der bei seiner Ent- 
stehung auf ihn einwirkenden Stoffe und Kérper voraus. 
“There can be little doubt, indeed, that every science as it progresses will 
become gradually more and more quantitative.” 
The book is divided into nine chapters. The first deals with the action 
of chemical agents upon protoplasm, and it is here especially. that the great 
value of exact quantitative work becomes apparent. The third section, 
devoted to chemotaxis (chematropism), is doubtless one of the most attrac- 
tive in the whole work. Pfeffer’s classical experiments are quite fully 
related. 
: ‘rom the second to the eighth chapters the author treats of the effects 
__ of (1) moisture, (2) density of medium, (3) molar agents, (4) gravity, (5) elec- 
ee, (6) light, and (7) heat. In general it may be said that a fair historical 
iew is given of the literature on these subjects. In a few cases, it is our 
Opinion that better illustrative experiments could have been chosen. In 
: _ Some cases too much space is given to the Protista, to the exclusion of ne 
_ Metazoa. This is especially so in the section on sterec otaxis (sterec opisi De 
where only a bare reference is made to th -otaxis of multicellula f 
f Voimdyoulgpers ch, Experimental — bs art L _ Svo. pp. xiv -[-280 
New York: The Macmillan a ($2.60. a | 
