242 APPEXDIX 



least as good as the grade known as ledger 17 x 22 — 32. The J. L. 

 Haiiimett Coiiipauy (educational supply), Boston, can furnish books 

 of this paper. SxlO, 100 page.s, with flexible covers, at iO cents eacli, 

 more or less, if ordered in lots. 1 mention this to give some notion 

 of the probable cost of such books. 



The Laboratoiy Studies have been written Avith a view to tlie use 

 of the dissecting microscopie, or liand lens, solelj'. But it is evident 

 that one or two compound microscopes may be the means of adding 

 greatly to the interest of the pupils. Demonstrations of the minute 

 structure of the higher plants, in the course of the study of the chap- 

 ter on that subject, demand the compound instrument. How far one 

 may profitably go into the study of celhdar structure depends upon 

 circumstances, such as the age of the pupils and the time at their dis- 

 posal. Personally, I believe that, especially if the teacher has used 

 the compound microscope much, he will be likely to underestimate 

 the difficulties of gaining true impressions of the structure as it e.xists 

 in three dimensions, from sections necessarily showing but one plane 

 at a time. 



Material. — The material for study, when not named and described 

 in the exercises themselves, is specified in the Appendix. 



Material in stock. — Dried and pressed specinjens, supplementary to 

 tlie laboratory and the text, should lie mounted on stiff board of con- 

 venient size. Herbarium papei' is loo flexible and too large for hand- 

 ing around. 'J'he collecting instinct is strong, and tlie successive 

 classes in botany niay be called upon to build up such a collection as 

 is desired, in the case of schools in or near the open country. Valu- 

 able suggestions as to collecting and mounting illustrative material 

 is given by Dr. Ganong in the '■ Teaching Botanist." 



Material not dried may be preserved in formaline (formaldehyde) 

 of 4%. As sold, this preservative is of 40%. It is cheaper, when 

 dilute, than alcohol, but the fumes are disagreeable and harmful, so 

 that material to be woiked oxer should be well soaked and freed from 

 formaline. Alcohol is the best preservative. Fiftj' per cent may be 

 strong enough to keep material for general morpliological work; but 

 70% is better. 



Study and drawing. — The aim of laboratory work in botany is to 

 win an insight into the life of plant.s as revealed in structure, or as 

 manifested by living plants under observation in the experiments. 

 Structure is the record of past and present natural history. It repays 

 thoughtful consideration. 'I'he simple drawing of the material pre- 

 sented is by no means an adequate method of dealing with it. It is 

 common to see students ilraw assiduously and well, while passing on 

 from one subject to the next, with little or no comprehension of the 

 meaning of the forms. It is not unusual to see careful drawings, on 

 which much time has been piut, which illustrate accidental, abnormal. 



