Botany and Zoology. 155 



2. Principles of Botany ; by Joseph Y. Bergen and Brad- 

 ley M. Davis. Pp. ix + 555 ; 394 text-figures. Boston and New 

 York, 1906 (Ginn & Company). — Bergen's "Foundations of 

 Botany," published in 1901, has been one of the most widely 

 used botanical text-books for secondary schools. The present 

 volume includes the best features of the earlier work, but is 

 enlarged in scope so as to become available for more mature 

 pupils. At the same time, by confining the attention of the 

 student to certain selected chapters, the book may still be used 

 in an elementary course. It is divided into three parts : — I. 

 The Structure and Physiology of Seed Plants ; II. The Mor- 

 phology, Evolution and Classification of Plants ; III. Ecology 

 and Economic Botany. The first and third were written by Mr. 

 Bergen, the second by Dr. Davis. The first part is taken almost 

 directly from the " Foundations," although there are several 

 changes in arrangement. The second part, which contains the 

 most new matter, not only describes a series of instructive types 

 from the Algae to the Angiosperms, but discusses a number of 

 topics of general botanical interest, such as the evolution of sex, 

 the alternation of generations, the development of heterospory, 

 and the origin of the seed-habit. The whole is treated with the 

 utmost clearness, but it is possible that some of the subjects 

 introduced may be too abstruse for the average student. In the 

 third part the chapters on ecology have been largely rewritten, 

 and a brief account has been added of the phenomena of muta- 

 tion and variation, together with the methods of plant breeding. 

 The part concludes with a description of the most important 

 economic plants of both temperate and tropical regions. 



a. w. e. 



3. Second Report of the Wellcome Research Laboratories at 

 the Gordon Memorial College, Khartoum / by Andrew Bal- 

 eour, Director. Department of Education, Sudan Government, 

 Khartoum. 1906. Pp. 255, with 16 colored plates and 106 

 figures and maps. — This volume embraces the results of the work 

 of the staff and collaborators of the laboratories during the past 

 two years. This work has been of the greatest practical import- 

 ance as well as of scientific value, embracing as' it does the study 

 of the conditions which render the Sudan somewhat unfavorable 

 for the habitation of civilized races. The interesting account of 

 the work of the mosquito brigade and the regulations to prevent 

 steamers and other boats bringing mosquitoes into Khartoum, 

 indicates what a comparatively simple matter it would be for sec- 

 tions of the United States which are now afflicted with malaria, 

 to eliminate at once the anopheline mosquito and the parasitic 

 disease which it may convey. 



The chapter on biting and noxious insects other than mosqui- 

 toes deals with the species of tsetse fly which carries the parasite 

 which causes the fatal trypanosomaisis of animals and the one 

 which is the agent of transference of the human trypanosome, 

 supposed to be the cause of the dreaded " sleeping sickness." Bot 



