if carelessly written ones are accepted by the teacher, but most 

 pupils will write notes which come up to the standard maintained 

 by the teacher. 



Notes and drawings should be collected, examined, and graded 

 weekly, and they should be returned to the pupils promptly. By 

 this means errors are detected at once, and any tendency to 

 postpone note-writing may be corrected. 



The amount of drawing which is called for in this manual is 

 not great, and most of the necessary drawings should be dia- 

 grammatic. The results of investigation *of the psychology of 

 drawing in biological study have shown 1 that there is little 

 pedagogical value in the detailed drawings the making of which 

 formerly occupied such a large place in biological courses, but 

 that diagrammatic drawing is a very valuable teaching device. 

 Diagrams are properly employed to represent the pupil's ideas 

 regarding the relations of things ; detailed drawing, to make clear 

 such descriptive facts as cannot be readily represented in words. 



It has been found advantageous to take the class out of the 

 laboratory and into the field, forest, or garden for many exercises 

 which are sometimes worked out within the laboratory, and cer- 

 tain other exercises ought, if possible, to constitute home proj- 

 ects, as indicated in connection with the exercises. It is always 

 preferable to take the class to the materials in their natural 

 surroundings rather than to bring the materials into the labora- 

 tory, if the former course is practicable. Each outdoor excursion 

 made by the class should be directed to the solution of a definite 

 problem and should be characterized by the same kind of serious 

 work as characterizes ordinary laboratory sessions. Such short 

 excursions, restricted to a single problem, ar% better assimilated 

 than are longer and more or less confused excursions. They 

 offer the further advantage of avoiding the administrative diffi- 

 culties which have sometimes put field work in disfavor. 



No directions are given for all-day field trips. Such extended 

 excursions should be planned whenever possible, but local con- 

 ditions vary so widely that it is obviously impossible to write 

 directions that will be generally applicable. The botanical results 

 1 F. C. Ayer, Psychology of Drawing. Warwick and York. 



[v] 



