72 REVIEWS. 



stances, are : 1, the limitation of species, and consequently of 

 genera and families, in every country where they now appear ; 

 2, the distribution of the individuals of a species in the 

 country it inhabits ; 3, the geographical origin and extension 

 of cultivated species ; 4, the naturalization of species and the 

 opposite phenomenon of their increasing rarity ; 5, the disap- 

 pearance of species contemporaneous with man. 



" In all this we observe proofs of the greater influence of 

 primitive causes, and of those anterior to our epoch ; but the 

 growing activity of man is daily effacing these, and it is no 

 small advantage of our progressing civilization that it enables 

 us to collect a multitude of facts of which our successors will 

 have no visible and tangible proof." 



An Appendix, indicating the researches now needed for the 

 advancement of Geographical-botanical science, under several 

 heads, addressed respectively to physicists and meteorologists, 

 to geographers, to geologists, to vegetable physiologists, de- 

 scriptive and traveling botanists, and to philologists, brings 

 these most interesting volumes to a conclusion. 



Our present object is to call the attention of American nat- 

 uralists and natural philosophers to this work, not to criti- 

 cise it. That would require much consideration and a wider 

 range of knowledge than we can pretend to. There are, how- 

 ever, several topics upon which w^e are inclined to venture a 

 few remarks, as fitting opportunities occur. 



HENFREY'S BOTANY.^ 



This is a well-planned, compact, and comprehensive work, 

 in w^hich we may say, that the author has fairly accom- 

 plished his purpose, namely : — "to produce a good working 

 text-book for the student, from which may be obtained a 

 groundwork of knowledge in all branches of the science, 



1 An Elementary Course of Botany ; Structural, Physiological, and Sys- 

 tematic ; icith a brief Outline of the Geographical and Geological Distribu- 

 tion of Plants. By Arthur Henfrey. London, 1857. (American Journal 

 of Science and Arts, 2 ser., xxiv. 434.) 



