210 THE JOURNAL OF BOTANY 
NOTICES OF BOOKS. 
Physiologische Pflanzenanatomie. By Dr. G. “opr: Dritte 
Aufiage. Leipzig: Engelman 
Histonoeicat features of plants may be ii with merely as 
structural details that are to be faithfully described regardless of 
_ _— ce ea The subject of histology, treated in 
s ma remai i i 
to the investigator a useful encyclopedia. But histology regarded 
either from a i baw peop or a physiological standpoint, or from 
ecomes one of the most stimulating and important branches 
of botany. It is, ainceee, not always possible to decide whether 
the ons ert of definite histological details be phylogenetic or 
physiological ; nee oe histological text- — written from 
either of these points of view are necessarily more or less narrow 
and incomplete. fe instance, be Pyrat: Haberlandt’s book we 
neither expect nor do we r ade at account of modern 
investigations on ‘the stelar ceyinine. of stems. What we do anti- 
cipate is a sufficient presentation of a sian ly modern account 
of the relations i gp the structure a i— of the vegeta- 
tive tissues of plants, and this we do ree 
he present edition of this well- panera text-book shows the 
widest difference from the preceding edition in the ¢ 
motor and irritable mechanisms, upon which the author is entitled 
to write with the high authority of'a pioneer. The chapter 3 
pened organs is enriched by an account of motor mechanism 
Ww action is determined by the cohesive force of water canned 
in cell-tumina, as distinguished from lifeless mechanisms whose 
deals vuceeeeee with tactile organs (tactile pits, herr and 
hairs), organs (with statocysts and statoliths) capable of perceiving 
gravitational stimuli, and, finally, organs for the perception of light. 
- In the chapter on the arrangements for the transmission of stimuli, 
the author first deals with protoplasmic transmission, 3 discusses 
the supposed differentiation of protoplasmic fibrille for this purpose ; 
and, secondly, he selects Mimosa pudica as a type to ot what 
we may term the hydrodynamic propagation of im 
: Additions to the body of the text, and to the iin cour. 
ae ing the citation of literature, have also been made throughout the 
book. That all these should be complete is too much ‘to expect, 
when we consider the vast field covered. The short account of 
oe “myeorhiza, for instance, is neither up to date nor is it sufficiently 
critical. Nor can it be said that the author has always escaped 
mature special pleading. His account of the structure and functions 
f the laticiferous system is hardly a judicial survey of the available 
