Botany and Zoology. 87 



greatly encouraged when botanists discovered that such observa- 

 tions might, also, be useful to classification, and it is no exagger- 

 ation to say, that the anatomical method has brought out a keener 

 interest in the study of anatomy, than if plant-structures were 

 worked up for the mere sake of learning how plants are built. 



Never before have botanists cared to give so many detailed 

 accounts of the internal structure of the reproductive and vege- 

 tative plant-organs as they do now, and moreover, this same 

 method has given rise to another still more modern branch of 

 Botany, generally known as " ecology," which has attracted so 

 much attention lately. From the knowledge of the structure, 

 considered by itself, investigations have been broadened into the 

 study of its application to systematic botany, while at the same 

 time these same anatomical characters have thrown light upon 

 the connection between these and the conditions under which 

 plants live. But investigations of that kind require long time 

 and steady attention, and it is very complimentary to European 

 botanists that so much work has already been accomplished in 

 this line : " the anatomical method." The large number of 

 papers published upon the subject are, however, very scattered, 

 and there has been great need for a book in which all the facts 

 hitherto known, were brought together in systematic form. It 

 must be said that the author has been very successful in his com- 

 pilation of this enormous material to which he has himself con- 

 tributed extensively. Besides giving a skillful and thoroughly 

 scientific representation of the anatomical characters of dicotyle- 

 donous plants, the author has rendered excellent service to fur- 

 ther studies by appending a bibliography to each of the orders 

 treated. It would be impossible to review all the results which 

 are laid down in this book, inasmuch as it is not a book to be 

 simply read, but to be studied. A very detailed account is given 

 of each order, including a large number of genera and species, 

 and much can be learned about the anatomy of the root, the 

 stem and the leaves, as these have been treated in their various 

 modifications. The anatomical characters are represented as 

 generic or specific, and it is very interesting to see the great vari- 

 ation that exists in a number of species, even of the same genus, 

 when we consider, for instance, the mere structure of epidermis 

 with its stomata and hairs, which furnish so many and such prom- 

 inent distinctions. Very important characters are, also, derived 

 irom the modifications that are frequently met with in the 

 mesophyll of the leaf or the bark of the stem with its reservoirs, 

 as cells or ducts, the contents : crystals or liquids ; moreover, 

 the very varied development of the mestome in root, stem and 

 leaf, the structure of the pith, etc. 



But when we look at the material, upon which these investiga- 

 tions are based, it is at once noticed, that only a relatively small 

 number of North American plants have, so far, been studied 

 from this viewpoint. This ought to give an impulse to similar 

 studies in this country, inasmuch as the North American vegeta- 



