XXXVI SCIENCE PROGRESS. 



astonishing to find that all the dimensions are given subject to the 

 assumption that the permeability of the medium is without dimensions 

 being merely a ratio. The inclusion of the permeability and specific 

 inductive capacity in the dimensional equations seems as if it would 

 never find its way into any elementary text-books. 



The translation is everything that could be desired, the English 

 being clear and not defaced by the German construction of the sen- 

 tences so often found in translations. Dr. Burton has added here and 

 there explanatory sentences (indicated by square brackets). In one or 

 two places, however, these additions might have been considered as 

 corrections and introduced into the text, for at present there are a few 

 rather laughable sentences formed by the combination of the translator's 

 addition with the author's original statement. Thus on p. 277 we 

 read : "... A current of one ampere produces at a distance of i cm. 

 from its axis a field-intensity of i of an absolute unit, supposing the 

 permeability to have the value unity [or any other value] ". 



Physiologische Pjlanzeiianatoinic , von Dr. G. Haberlandt, O. O. Pro- 

 fessor der Botanik, vorstand des Botanischen Institutes und 

 Gartens a. d. k. k. Universitat Graz. Zweite, neubearbeitete 

 V. vermehrte auflage, mit 235 Abbildungen. Leipzig, Wilhelm 

 Engelmann, i8g6. 

 The publication of Dr. Haberlandt's Physiologische Pflanzenanatomie 

 some twelve years ago marked a new departure in the general treat- 

 ment of anatomical facts. Naturally the author did not himself 

 actually initiate the movement of which his book was the outcome, but 

 he was perhaps the first who gave a clear and general exposition of the 

 old facts regarded from the new standpoint, and the results have fully 

 justified his efforts. Anatomical characters, no doubt, oftentimes possess 

 an intrinsic importance of their own, even from a taxonomic point of 

 view ; that is, they may possess even a high value in certain cases, as 

 in a measure indicating phylogenetic affinities. But no one will deny 

 that in the vast majority of cases one is on ver}' unsafe ground in 

 attempting to show phylogenetic conclusions from such a source. 

 And this being so, it is obvious that plant anatomy is in some de- 

 gree robbed of an interest which renders the study of the comparative 

 anatomy of animals so interesting. But, on the other hand, the botanist 

 gains on account of the great extent of individual {i.e., within the same 

 species) variation exhibited by plants, and the marked correlation which 

 may be seen to exist between the organism and the special kind of en- 

 vironment in which it happens to be located. A plant cannot often 

 grow where it will but where it must. Hence the continuous need of 

 a possibility of variable response to conditions which themselves vary. 

 Thus it is that plant anatomy is so closely bound up with the circum- 

 stances of the passive environment, and that its study, from this point 

 of view, constitutes one of the most fascinating branches of investigation, 

 although the ulterior question as to how it is possible for an organism 

 to have become possessed of the power of responding in a purposeful 



