Botany and Zoology. 105 



tive manual, is by Professor Pammel himself, and provides full 

 descriptions of the weeds represented, together with figures, notes 

 on distribution, and directions for extermination. The second 

 chapter describes the gross structure of the seeds of the weeds, 

 the third chapter the microscopic structure of certain selected 

 seeds, and the fourth chapter includes a full account of the 

 morphology of the leaves and flowers of weeds. In the remain- 

 ing chapters the dissemination of weeds, the morphology of the 

 underground portions, the injuriousness of weeds, and the migra- 

 tion of weeds are among the topics treated. The numerous 

 illustrations, which are partly original and partly taken from 

 other publications, add greatly to the value of the volume. 



a. w. E. 



2. Researches on the Irritability of Plants; by Jagadts 

 Chunder Bose. Pp. xxiv, 376; 190 text figs. New York, 1913. 

 (Longmans, Green & Co.) — In this volume Dr. Bose continues his 

 interesting and original studies on the responses of plants to 

 stimuli and describes improved and delicate apparatus by means 

 of which the responses may be more accurately recorded. The 

 plants most used in his investigations were the sensitive plant, 

 Mimosa, and the remarkable Desmodium gyrans, and the stimuli 

 employed were of many different kinds. By means of his 

 apparatus he was able to demonstrate the latent period of a 

 response as well as its various phases, and most of his figures 

 represent actual records of responses made by himself and by his 

 students. One interesting conclusion which he draws from his 

 investigations is that the various manifestations of irritability 

 shown by plants are identical with those shown by animals, and 

 he suggests that many difficult problems in animal physiology 

 may find their solution in the study of the more simply organized 

 plants. a. w. e. 



3. Introduction to Botany ; by Joseph Y. Bergen and Otis 

 W. Caldwell. Pp. vii, 368 ; 246 text figs. Boston and New 

 York, 1914. (Ginn & Company.) — In this elementary text-book, 

 designed for pupils in secondary schools, the authors aim to 

 present those features of plant life which are of interest to all 

 people. The plant is considered as an independent organism, 

 which has its own living to make under varied circumstances. 

 The forms selected for description and illustration are for the 

 most part those seen in everyday life and those of economic 

 importance. The figures, many of which are original, are 

 unusually clear, and an interesting feature of the work is the 

 introduction of portraits of famous botanists. The book main- 

 tains the high standard set by the authors in their earlier publica- 

 tions and may be cordially recommended to teachers, a. w. e. 



4. Wissenschaftliche Ergebnisse der Deutschen Zentral- 

 Afrika- Expedition 1907-1908, unter Fuhrung Adolf Friedrichs, 

 Herzogs zu Mecklenburg. Leipzig, 1914 (Klinkhardt and Bier- 

 mann). — Vol. II, Botany, edited by Dr. J. Mildbraed, Berlin. 

 Lieferung 1, pp. 603-718. The earlier parts of this valuable work 



