244 



SCIENCE 



[N. S. Vol. XXXIV. No. i 



to assimilate and act upon the stores of knowledge 

 which have been accumulated through the cen- 

 turies, then it is the gamete that we must consult. 

 The saving grace is with the gamete, and with the 

 gamete alone. 



W. E. Castle 

 Haevaed University 



Plant Physiology, with Special Reference to 

 Plant Production. By Benjamin M. Dug- 

 gar. 13 X 20 cm. Pp. XV + 516, frontis- 

 piece and 144 figures. The Eural Text- 

 book Series. New York, The Maemillan Co. 

 May, 1911. Price $1.60. 

 The grovfing realization that a rational 

 agriculture must rest upon the principles of 

 plant physiology finds definite expression in 

 the appearance of Professor B. M. Duggar's 

 new text -book. As the title implies, this book 

 is intended for agricultural students and those 

 primarily interested in " plant production," 

 and it should occupy a very necessary and 

 permanently useful place in American agri- 

 cultural colleges and experiment stations. 



The choice of subject matter is governed by 

 the centering of the entire treatment about 

 the idea of the usefulness of plants in human 

 affairs, so that relatively great importance is 

 accorded those aspects of physiology which 

 enter into present agricultural, horticultural 

 and silvicultural theory and practise. Plant 

 physiologists may be surprised to find that 

 other portions of our present physiological 

 knowledge are often but briefly and sum- 

 marily treated. Thus, the whole subject of 

 movements due to growth receives only about 

 ten pages, while over twenty-six pages are 

 devoted to variation and heredity, subjects as 

 yet hardly to be considered as more than 

 purely descriptive physiology. Many topics 

 not usually treated under physiology find 

 place here, and many illustrative examples are 

 drawn from agricultural experience, so that 

 the book should serve not only as an introduc- 

 tion to things physiological for those who care 

 mainly for the practical manipulation of 

 plants, but also as a key to many important 

 agricultural points for those to whom etiolog- 

 ical physiology is of primary interest. The 



book should therefore find a considerable use, 

 also, in university laboratories. Enough ex- 

 cellently chosen titles are cited from the lit- 

 erature so that the more thorough-going stu- 

 dent may find the book an adequate point of 

 departure in the acquisition of a first-hand 

 knowledge of the deeper aspects of the subject. 



The literary style of this treatise is fre- 

 quently abrupt and fragmentary, sometimes 

 ambiguous. Technical terms are now and 

 again introduced without previous explana- 

 tion, the reader being left to surmise their 

 meaning from the context ; also the paragraph 

 often lacks unity. A few examples of am- 

 biguity may be noted. On page 58, regarding 

 Tillandsia, we read that it " is provided with 

 much the same type of water-absorbing hairs 

 which give the entire surface a glistening ap- 

 pearance." Hairs have not been mentioned 

 previously in this section, so that the refer- 

 ence of the word same is not evident. A 

 comma should precede which. Again, on page 

 65 we find, " this diffusion is wholly inde- 

 pendent of any convection currents due to 

 changes in temperature, and it is true for all 

 such soluble substances as sugar, common salt 

 and the like." Here the personal pronoun is 

 without antecedent. On page 195, in the sen- 

 tence, " As organic matter so called, this ele- 

 ment is linked chiefly with hydrogen," etc., 

 " this element " has been mentioned only in 

 the chapter title, " The intake of carbon," etc. 



Some surprising inaccuracies occur, several 

 of which may be mentioned here. At the 

 bottom of page 207 " bioses " is obviously in- 

 tended to denote disaccharide hexoses. The 

 word " hydroscopic," page 245, should be hy- 

 groscopic. In the last paragraph of page 264 

 the word " hemlock " is used to refer to Ahies 

 alba, which it is not. On page 294, a propos 

 of certain " roots or root branches which seem 

 to be important in aeration," it is stated that 

 " to these organs the term hydathodes has 

 been applied " : this word is applied to certain 

 peculiar foliar openings or water pores, 

 through which guttated liquid escapes. On 

 page 402 barley is mentioned as " almost un- 

 knovsm southward," yet it is one of the main 

 hay crops of the southern portions of Arizona 



