no 



SCIENCE. 



[N. S. Vol. V. No. 107. 



thing new to say, something based upon experi- 

 ences and observations. These are by no means 

 all his own, for he has the ability to see with 

 the eyes of other people, as well as with his 

 own. He is thus able to bring into his pages a 

 rich mass of new matter which giv.es them ad- 

 ditional interest and value. 



This new book consists of essays and papers, 

 all of which have been presented elsewhere and 

 are now brought together in accordance with 

 the author's plan. Thus, while a collection of 

 essays, it is not without unity. ' ' In making 

 these essays," the author says in his preface, 

 ' ' I have constantly had in mind their collection 

 and publication, and have therefore endeavored 

 to discuss the leading problems associated with 

 the variation and evolution of cultivated plants, 

 in order that the final collection should be 

 somewhat consecutive." 



The following sentences from the preface will 

 give the reader a general idea of the author's 

 position. "The underlying motive of the col- 

 lection is the emphasis which is placed upon 

 unlikenesses, and of their survival because they 

 are unlike. The author also denies the common 

 assumption that organic matter was originally 

 endowed with the power of reproducing all its 

 corporeal attributes, or that, in the constitution 

 of things, like produces like. He conceives 

 that heredity is an acquired force, and that, 

 normally or originally, unlike produces unlike." 

 The author's a priori reasons for belief in the 

 hypothesis of evolution are "the two facts that 

 there must be struggle for existence from the 

 mere mathematics of propagation, and that 

 there have been mighty changes in the physical 

 character of the earth, which argue that organ- 

 isms must either have changed or perished." 

 On the other hand, "the chief demonstrative 

 reason for belief in evolution is the fact that 

 plants and animals can be and are modified 

 profoundly by the care of man." 



The body of the book is in three ' parts, ' the 

 first including essays touching the general fact 

 and philosophy of evolution; second, those ex- 

 pounding the fact and causes of variation, and 

 third, those tracing the evolution of particu- 

 lar types of plants. The first essay gives name 

 to the book. In it the author discusses (1) the 

 nature of the divergences of plants and animals. 



suggesting the Mycetozoa as the point of diver- 

 gence; (2) the origin of differences, holding 

 that all plants and animals came from one 

 original life-plasma which had the power of 

 perpetuating its physiological but not its struc- 

 tural identity; no two organisms ever being 

 exactly alike, it follows that unlike produces 

 unlike; (3) the survival of the unlike, this being 

 an extension of our notion of the meaning of 

 the phrase ' the survival of the fittest,' by show- 

 ing that the fittest are the unlike. 



The author gives us some interesting pages 

 on the species dogma, in which he pointedly 

 shows the inconsistency of those who demand 

 experimental evidence of the evolution of a 

 species, and yet reject ' horticultural species ' 

 because they have been produced under cultiva- 

 tion. Many examples are given of the origina- 

 tion of well-marked 'varieties,' which are more 

 different from the species from which they 

 sprung than are the recognized species from one 

 another. Here Professor Bailey's experience 

 as a horticulturist enables him to cite striking 

 examples of what the candid reader must admit 

 are good species evolved through man's selec- 

 tion. Thus we seem to have made species of 

 of beans (Phaseolus), tomato (Lycopersioum), 

 maize (Zea), soy-beans (Olycine), etc. The 

 horticulturist who is familiar with the plasticity 

 of plants, and who is accustomed to see new 

 and persistent forms arise, cannot help being 

 an evolutionist, nor can he help being impatient 

 with the botanist who refuses to accept such 

 forms as true varieties or species, as much en- 

 titled to recognition as those whose origin we 

 do not happen to know. 



Charles E. Bessey. 



The University of Nebraska. 



A Popular Handbook of the Ornithology of Eastern 

 North America. By Thomas Nuttall. 2d 

 Revised and Annotated Edition, by Mon- 

 tague Chamberlain. With additions and 

 110 illustrations in colors. Vol. I., The Land 

 Birds. Vol. II., Game and Water Birds. 

 Boston, Little, Brown & Company. October, 

 1896. 



For more than half a century students of 

 North American ornithology have had three 

 works which by common consent came to be 



