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PREFACE 



Practical Biology offers a simple, workable, attractive, 

 flexible, and teachable course in Biology. 



Simplicity is a feature of the book. The language is simple, 

 not technical, and the style is easy, flowing, and colloquial. 

 The pupil is assisted by many mechanical helps. Small cuts 

 or larger pictures illustrate each new topic and there are many 

 charts and maps. 



The practical aspects of Biology are emphasized. A study 

 is made of the economic value of plants and animals, and of 

 the characteristics which make them beneficial or harmful to 

 mankind. * 



The attractive illustrations, many of which were made es- 

 pecially for the book, are a feature of the Biology. In addi- 

 tion to the cuts and pictures which illustrate the text, there 

 are portraits of the leading biologists of the world, with brief 

 accounts of their lives and of their contributions to the subject. 



The flexibility of the book enables teachers to begin with 

 the study of animals or with the study of plants. 



A number of features help to make Practical Biology teach- 

 able, (a) The paragraphs are short, and there are summaries 

 and questions at the end of each chapter, (b) Well-known 

 types like the grasshopper and the bean plant are studied first, 

 and the treatment passes from the known to the unknown, 

 (c) The pronunciation and derivation of technical names are 

 given in the text the first time the names occur, (cl) There is 

 an introduction defining the common scientific terms used in 

 the study of Biology, (e) Optional field work and students' 

 reports are provided for. (/) Laboratory work is contained 



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