Preface 



Permanent slides for microscopic study are indispensable in the 

 teaching of a basic course in botany and also in specialized advanced 

 courses. In some advanced courses, the students prepare many of the 

 slides used in the course, but in elementary courses the slides are 

 furnished. In the latter case, the slides either are purchased from 

 commercial somxes or made in the departmental laboratory. Biologi- 

 cal supply houses make excellent slides of the subjects commonh used 

 in elementary teaching, but the quality is likely to be variable. 

 Jobbing houses that pinxhase slides from constantly changing sources 

 also may furnish disappointing slides at times. 



The relative merits of making slides and of purchasing them 

 must be decided on the basis of local conditions. Uncertainties in the 

 commercial supjih and the need for specialized or unlisted items 

 necessitates the preparation of slides in the biological departments 

 of schools. This service work often is performed by a skilled profes- 

 sional technician with more or less supervision by the departmental 

 staff. In other departments a member of the teaching staff, usually 

 a morphologist, assumes this responsibility, with the aid of student 

 assistants. 



Some research organizations maintain a technician for the prepa- 

 ration of research slides. There are many types of investigation in 

 which it is possible for the technician to prepare and place the 

 finished slides before the in\estigator, who then carries out the study 

 and interpretation of the material. However, in many investigations, 

 some or all steps in the preparation recjuire an intimate knowledge 

 of the history, structure, and orientation of the material and the aims 

 of the study. The use of a technician who allegedly merely "turns 

 the crank" is then less valid, and the so-called technician may in fact 

 be a research collaborator. The in\estigator in any field of plant 

 science is urged to utilize microtechnique as a tool, but to do so 

 critically and intelligently and in proper fairness to the workers who 

 contribute their skill, patience, and understanding to the furtherance 

 of the research. It cannot be too strongly emphasized that in order to 



[vii] 



