April 24, 1914] 



SCIENCE 



615 



it niakes an admirable reference book. 

 Czapek has also refused to assume the role 

 of arbiter, but quotes, with as little prejudice 

 as can be expected, the opinions of each indi- 

 vidual, leaving it to the reader to arrive at his 

 own conclusion. 



In closing, a single allusion to the greater 

 importance that is being accorded to phyto- 

 chemistry in recent years may not be out of 

 place. For more than a generation after the 

 announcement of the benzene theory by 

 Kekule, organic chemists could think of little 

 else than synthesized substances and of coal 

 tar as their gold mine. So one-sided were 

 they at times that they did not even see the 

 element of the ridiculous in the suggestion to 

 make foodstuffs artificially from this source. 

 The other extreme has now been reached by 

 the pure-food chemist who by big head lines 

 in the newspapers and the waving of red rags 

 before large audiences denounces this same 

 coal tar as the source of everything that is 

 bad. A much more common sense reaction 

 has been started by those chemists who have 

 been pointing out how the intricate process of 

 the plant laboratory may be husbanded for 

 the benefit of mankind by farmers who need 

 not be Ph.D.'s but who have been taught by 

 the biochemist to make the most of their 

 opportunities. 



Again, while we should welcome the new 

 synthetic remedies that have been turned out 

 by the " Farbenfabriken " of the fatherland, 

 we should not forget that in this field also the 

 plant still produces valuable remedies which 

 we can obtain as well or better from living or 

 recently dead plants than as a by-product from 

 fossilized plants of former geological ages. 



But aside from the agricultural and phar- 

 maceutical or medical aspects which the chem- 

 ical study of plants and plant life may afford, 

 the study of these subjects for its own sake 

 has a charm all its own. Who can view the 

 beautiful color of the flowers or inhale their 

 perfume without feeling that a knowledge of 

 the processes by which the plant produces 

 these physiological effects on the intelligent 

 animal is in itself worth knowing though the 

 pigment never be used to dye a fiber, nor the 



perfume be extracted in order to find a place 

 on my lady's toilet table Edwaied Kremers 



A History of Land Mammals in the Western 

 Hemisphere. By William Beeryman Scott, 

 Blair Professor of Geology and Paleontol- 

 ogy in Princeton University. New York, 

 The Macmillan Company, 1913. Pp. i-xiv + 

 1-693, with frontispiece and 304 text-figures. 

 In this striking volume Professor Scott has 

 striven to assemble and set before the lay 

 reader a judicious selection from the great 

 accumulation of facts which the many stu- 

 dents of mammalian paleontology have dis- 

 covered. The presentation of the subject is 

 essentially different from that of Professor 

 Osborn's " Age of Mammals " wherein the 

 rise and spread of faunas are treated as a suc- 

 cession of historical events. In the present 

 work, after certain introductory chapters, the 

 treatment is zoological, the life history of each 

 of a number of important orders being dis- 

 cussed from beginning to end. Thus the two 

 works by two of the foremost American pale- 

 ontologists are supplemental ; collectively they 

 give a complete picture of Tertiary time. 



The first two chapters of Professor Scott's 

 book acquaint one with the methods pursued 

 by the student of past life, the one showing 

 the way whereby the geological data are inter- 

 preted, and the other the methods of paleonto- 

 logical research — how animals are preserved 

 from the remote past, the nature of the re- 

 mains, the way in which the characters they 

 show are explained, and the method whereby 

 the animal is reconstructed as a living being. 

 A chapter on the principles of taxonomy is 

 conchided by a full mammalian classification 

 which is almost identical with that given by 

 Professor Osborn in the " Age of Mammals," 

 the only differences being relatively unimpor- 

 tant. The discussion of the skeleton and 

 teeth of mammals, so essential to an under- 

 standing of fossil evidence, is followed by a 

 chapter on the principles of geogTaphical dis- 

 tribution of mammals and a summary of the 

 successive mammalian faunas. 



The succeeding chapters elucidate the his- 

 tories of the principal orders : the Perissodac- 



