VI PREFACE 



science point of view. It is far from being merely a theo- 

 retical attack upon the problems of an introductory course 

 in biology, for a large part of the radically new arrangement 

 of subject matter has been worked out in practice by the 

 authors and by several other teachers who have worked under 

 suggestions from the authors. 



The authors trust that the critical readers whose attention 

 may be attracted to parts of this book which seem to depart 

 radically from the traditional introduction to biology, espe- 

 cially by means of separate courses in botany and zoology, 

 may be so kind as to frame their criticisms in the light of the 

 explanations and defense which have been written for an 

 accompanying " Teachers' Manual of Biology." See foot-note 

 on the first page of Chapter I. 



A noticeable feature of the book is omission or at least lack 

 of emphasis upon several hundred technical terms commonly 

 used in elementary books of botany and zoology. Italics have 

 been used for emphasizing the most important scientific terms 

 when introduced and defined, while technical words in the 

 plain type should be understood by students as important 

 for special study, for temporary use in the text, or for com- 

 parison with other books. The authors realize that in select- 

 ing the biological terms for emphasis they may have omitted 

 some really useful terms, and it may be that certain italicized 

 words which have a narrow range of application do not deserve 

 the emphasis given them. A further discussion of this ques- 

 tion of technical words will be included in the "Teachers' 

 Manual." 



This book also departs widely from the traditional teaching 

 of biological sciences, in that it presents much laboratory work 

 in the form of demonstrations by the teacher instead of 

 entirely as individual work for the students. This introduces 

 an important problem which can be adequately presented only 

 in the " Teacher s' Manual"; but the experience of many 



