166 



THE AMERICAN NATURALIST 



[Vol. XLVI 



THE DISTRIBUTION OF PLANTS IN NORTH 

 AMERICA 



A comprehensive account of the phytogeography of North 

 America has long been a desideratum, and it will be welcome 

 news to botanists that this need has at last been filled. The 

 work of Dr. Harshberger, 1 just issued, is an imposing volume, 

 which will be quite indispensable to all students of plant dis- 

 tribution, and evidently represents an enormous amount of 

 labor on the part of the author. A fair criticism that might be 

 made is that it perhaps is too comprehensive. The book in the 

 writer's opinion could have been very considerably reduced in 

 volume without lessening its value, by drastic cutting of the 

 first three parts, which arc really introductory, and yet take 

 up nearly half the book. The really essential facts concerning 

 the geology, geography and climatology of North America could 

 certainly have been presented in much less space. There is much 

 needless repetition, and the arrangement of the topics is at times 

 very confusing. 



In addition to Dr. Harshberger 's own work there is a summary 

 of the book, sixty-three pages in extent, written in German by 

 the editor of the series, Professor O. Drude. 



It is the fourth section of Dr. Harshberger 's book which will 

 undoubtedly be of most value to the average botanical student. 

 This deals with the North American phytogeographical regions, 

 formations and associations, and comprises an account of the 

 floras not only of the whole North American continent, but of 

 the West Indies as well. 



Nearly one hundred pages are devoted to the history of work 

 published on the floras of various parts of North America, the 

 bibliography alone comprising forty-six pages. This makes up 

 Part One of the work. The second part— Geographic, Climatic 

 and Floristic Survey — occupies seventy-seven pages. In this 

 section are given very much in detail an immense body of facts, 

 many of which could have been omitted without materially less- 

 ening the value of the summary. Nevertheless it contains very 

 much that the student will find exceedingly useful. 



This section makes very clear the great range of conditions on 

 the North American continent, which explains the richness and 

 variety of its flora. Very full statistics are given in this chap- 

 ^'Phytogeographic Survey of North America," John W. Harshberger, 

 ''Die Vegetation der Erde," Vol. XIII. 



