Botany and Zoology. 



429 



with Ostrcea subtrigonalis Evans and Shumard, also Melania, Paludina, 

 and other fresh-water shells, Corbula subtrigonalis, C. perundata. — Fort 

 Clark, Corbula mactriformis (associated with Melania, Paludina, etc.,) 

 Bulimus Limneiformis, B. Nebrascensis, Paludina multilineata, P. pecu- 

 liaris. — Little Horn River, Planorbis convolutus. — Yellow-Stone River, 

 30 miles above the mouth, Melania Anthonyi. — Near headwaters of Little 

 Missouri, Cerithium Nebrascencis.] 



III. BOTANY AND ZOOLOGY. 



1. Alph. DeCandolle : Geographie Botanique raisonnee, ou Exposition 

 des Faites principaux et des Lois concernant la Distribution Geograph- 

 ique des Plantes de V Epoque Actuelle. Paris and Geneva, 2 vols., 8vo, 

 1855. — Pressing engagements have prevented the fulfilment of our prom- 

 ise to make a detailed examination of this work. We exceedingly regret 

 this ; for the Geographie Botanique of DeCandolle is not only one of the 

 most important works of our day, but one which addresses and will 

 greatly interest, a much broader circle of scientific readers than any 

 other modern production of a botanical author. It is, and probably long 

 will be, the standard treatise upon a wide class of questions, highly and 

 almost equally interesting to the botanist, the zoologist, the geologist, the 

 ethnologist, and the student of general terrestrial physics. To its produc- 

 tion the author has devoted no small portion of the best years of his life ; 

 and it bears throughout the marks of untiring labor, directed by a re- 

 markably sound, conscientious, and thoroughly systematic mind. Along 

 with the admirable methodical spirit which is his by rightful inheritance, 

 the younger DeCandolle brings to these. investigations a particular aptitude 

 for numerical and exact forms, an intimate acquaintance with general 

 physical science, and considerable ethnological and philological learning; 

 which last is turned, to good account in his chapters on the history of cul- 

 tivated and naturalized plants. The result in the work before us, — even 

 if there were no other claims to the distinction, — may fairly be said to 

 go far towards inscribing the name of DeCandolle anew in that select 

 list of philosophical naturalists in which his father holds so eminent a 

 position. 



To give some idea of the topics considered in these volumes, and of the 

 order of investigation (which proceeds in an admirable course, from the 

 more simple, general, and better known facts and principles towards the 

 more complex, hypothetical and obscure), we will copy the titles of the 

 chapters, twenty-seven in number ; which are arranged in four books, and 

 subdivided into articles, and these again into sections, to such an extent 

 as to fill eight closely printed pages with the bare enumeration. Indeed, 

 this repeated subdivision gives a rigid and rather tedious aspect to some 

 parts of the work, and involves occasional repetitions ; but it would not 

 be easy to collocate well and clearly so vast an amount of materials in 

 any better way. 



The first Book is occupied with some preliminary considerations upon 

 the way in which temperature, light, and moisture act upon plants. Its 

 three chapters treat of the relations of plants to surrounding physical 

 conditions, and especially to heat and light ; and contain the author's 



