ANNOUNCEMENT. 



SINCE 1886, when the Handbook oj Plant Dissection 

 was published, both the methods of laboratory work and 

 knowledge of the plant kingdom have very materially 

 changed. The authors thought that any demand for 

 the book would have disappeared long since, but con- 

 tinued sales have forced them to the conclusion that in 

 justice to the subject and also to themselves a revision is 

 necessary. In morphological instruction the very detailed 

 study of a few types has given place to a study of the 

 most significant features of a considerable number of 

 types; and the accumulation of somewhat unrelated 

 facts has been succeeded by the attempt to organize the 

 facts into a connected account of the evolution of the 

 plant kingdom. 



An adequate revision, therefore, meant a complete 

 rewriting, and this the original authors were unable to 

 undertake. Accordingly they have delegated it to one 

 whose contact with laboratory work in elementary mor- 

 phology is fresher and has proved to be in every way 

 successful. 



The book is a new one, although developed in accord- 

 ance with the old plans, and it will far more worthily 



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