DEVELOPMENT OF BOTANY SINCE 1818 447 



influence upon the progress of botany in the United 

 States was largely due to his connection with the Journal. 

 His reviews extended over a very wide range, and supple- 

 mented to a remarkable degree his other educational 

 work. It must be permitted to allude here to his sagacity 

 as a writer of educational treatises. In his first ele- 

 mentary text-book, published in 1836, he expressed wholly 

 original views in regard to certain phases of structure 

 and function in plants, which became generally adopted 

 at a later date. His Manual of Botany was constructed, 

 and subsequent editions were kept, on a plan which made 

 no appeal to those who wanted to work on lines of least 

 resistance; in fact he had no patience with those who 

 desired merely to ascertain the name of a plant. In the 

 Journal he emphasizes the desirability of learning all the 

 affinities of the plant under consideration. At a later 

 period, when entirely new chapters had been opened in 

 the life of plants, he sought by his contributions in the 

 Journal to interest students in this wider outlook. 



Professor C. S. Sargent has selected with good judg- 

 ment some of the more important scientific papers by 

 Professor Gray and has re-published them in a con- 

 venient form. 1 Many of these papers were contributed 

 to the Journal in the form of reviews. These reviews 

 touch nearly every branch of the science of botany. As 

 Sargent justly says, "Many of the reviews are filled with 

 original and suggestive observations, and taken together, 

 furnish the best account of the development of 

 botanical literature during the last fifty years that has 

 yet been written." In these longer reviews in the 

 Journal, Gray was wont to take a book under review as 

 affording an opportunity to illustrate some important 

 subject, and many of the reviews are crowded with 

 his expositions. For example, in his examination of 

 vonMohl's "Vegetable Cell" (15, 451, 1853) he takes up 

 the whole subject of microscopic structure, so far as 

 it was then understood, and he points out the probable 

 errors of some of Mohl's contemporaries, showing what 

 and how great were MohPs own contributions to his- 

 tology. Such a review is a landmark in the science. The 

 physiology of the cell and the nutrition of the plant were 

 favorite topics with Professor Gray, and he brought 



