BOOKS AND CURRENT LITERATURE 93 



consists of grasses and sedges, and trees may be practically absent. Dry 

 savannas differ in aspect from wet savannas primarily in the presence 

 of scattered trees or clumps of trees (mostly Pinus rigida). It is in 

 these savannas that Tojieldia, Abama, and several other distinctive pine- 

 barren plants are found. The Cedar Swamp Formation represents the 

 common swamp type. Such swamps are extensively developed in 

 shallow depressions and low grounds along the sluggish streams of the 

 region. The character tree is Chaniaecyparis thyoides. Due to lum- 

 bering operations and other causes many former cedar swamps have 

 been superseded by deciduous swamps, but it should be noted that 

 many of the latter are apparently natural. The distribution of the 

 pine-barren, plain, savanna, and cedar swamp formations is indicated 

 in colors on the large map which accompanies the volume. 



The last half of the book is largely devoted to matters of autecologi- 

 cal interest. Among other things, there is a chapter (15) on the phyto- 

 phenology of the pine-barren vegetation, in which the flowering or fruit- 

 ing periods of practically all the pine-barren species are presented in 

 tabular form; a chapter (16) on vegetative propagation and the gross 

 structure of the shoot and root in typical pine-barren species, illustrated 

 by nearly fifty line drawings; a chapter (18) on leaf-forms of pine-bar- 

 ren plants, and another (19) on the microscopic leaf structure of more 

 than fifty species, all of which are figured in cross-section; a chapter 

 (20) on cone and seed production of the pitch pine, and viviparity in 

 Quercus marilandica; and finally a chapter (22) on pine-barren plants 

 from an evolutionary standpoint. Altogether the book probably rep- 

 resents the most comprehensive treatment of a relatively small area 

 from an ecological viewpoint that has ever been attempted in this 

 country. — George E. Nichols. 



Recent Text-books. — Two new text-books of botany have recently 

 come out which make very distinct appeals for recognition — the one' 

 by a college teacher of long experience and acknowledged success, the 

 other- by the efficient director of a botanical garden the main purpose 

 of which is to teach. In covers and contents the books are surprisingly 

 different from each other. The four hundred pages of Ganong's book 

 are bound in stiff boards, are abundantly illustrated from nature, the 



' Ganong, W. F., A Text-book of Botany for Colleges. New York, The Mac- 

 millan Company, 1916 ($2.00). 



* Gager, C. Stuart, The Fundamentals of Botany. Philadelphia, P. Blakis- 

 ton's Son and Company, 1916 ($1.50). 



