250 Beviews and Book-Notices. 



X. Eeviews and Book-Notices. 



A Text-Book of Botany.* 



Those who regarded this book with so much favor at the time 

 of its previous issue, eight years ago, will doubtless be gratified 

 that the fifth edition, with important revisions and additions, is 

 now accessible. That a work which has so well filled an impor- 

 tant place in botanical education, both in Europe and America, 

 should be kept well abreast of the most recent developments of the 

 science it represents , is particularly gratifying to those who have 

 realized that the former edition was in many respects sadly 

 behind the requirements of the day, almost as soon as issued, and 

 the name of the English editor is suflicient guarantee that all 

 reasonable effort would be made in this direction. 



The ground covered is extensive, dealing as it does with the 

 whole range of botanical science from histology to geographical 

 distribution ; and to comprise so much within the narrow limits 

 of an octavo of 480 pages has necessitated great abbreviation, 

 often when it would seem exceedingly desirable that more detailed 

 consideration should be given. Thus the very important results 

 recently developed concerning the continuity of protoplasm, are 

 dismissed (p. 31) with a brevity which must certainly leave a very 

 unsatisfactory impression on the mind of the student. Again, 

 concerning the movement of water, (p. 161) the student gains 

 but a superficial knowledge of the forces actually atwoik and 

 the way in which they operate, when it is stated that : " The roots 

 absorb a greater quantity of water than the plant requires, and 

 this therefore exercises ; pressure which drives the water that 

 has been already absorbed, higher and higher up the stem," — a 

 statement which is much too general to be exact, and which, in 

 the second place, gives the student no possible clue to the well- 

 known fact, that this root-pressure is largely subordinate to other 

 forces when the plant is in a condition of active transpiration. 

 Also, one is not informed of the important distinction which 

 must be made between the flow of sap which is purely mechanical 

 and that which is of a more strictly physiological nature. Thus, 

 the impression is given (p. 161) that the bleeding of trees is due to 



• Text-Book of Structural and Physiological Botany. By Otto W. 

 Thome and A. W. Bennett. Fifth edition 870., pp. 480. Longman, 

 Green & Co., London. 



