PREFACE TO THE THIRD EDITION Vll 



inner reactions be allowed, be complete, and be the student's 

 own, than that they be rigorously right. It is easy enough to 

 add new facts in order both to teach the pupil that conclusions 

 are liable to be wrong, and to force his conclusion closer to that 

 moving equilibrium which we call truth. This process is much 

 more easy than to re-galvanize the soul whose interest and 

 ability to reach conclusions have been aborted by a continual 

 denial of the right. Much of the failure in our laboratory work 

 is due to this "taxation without representation" in respect to 

 personality. 



5. On the other hand it is equally important that the work 

 shall not be confined to the field and the laboratory. "There 

 are many things in the infinite concourse of particulars which 

 we cannot afford to verify by experiment." The chief end of 

 laboratory work is gained for the elementary student when he 

 comes to appreciate the method and spirit by which sound in- 

 vestigation proceeds, has acquired enough technical skill to fol- 

 low elementary investigation on his own behalf, and has learned 

 how to appreciate, and if necessary to verify, the statements of 

 others. It is as easy to waste time in the laboratory as in reading 

 textbooks. 



6. The time in an elementary course should be about equally 

 apportioned (i) to laboratory work (chiefly in physiology and 

 in the larger problems of morphology rather than in minute 

 dissection); (2) to field observation on physiology, life histories, 

 and the simpler problems of distribution, classification, and 

 life relations; (3) to the body of the descriptive text; and (4) to 

 classes of questions demanding reference to classical zoological 

 authorities. 



It is a great mistake not to impress upon the student the 

 immense amount of work already done and to heighten his re- 

 spect for the library as one of his sources of information and 

 interest. 



7. The matter of greater native interest should underlie and 

 sustain that of less. It should not, however, exclude or efface 

 the latter. The most interesting is often the least important. 



8. Certain of the general facts and principles which the 

 beginner cannot be expected to discover for himself should be 



