Journal of 



Applied Microscopy. 



VOLUME II. JANUARY, 1899. NUMBER 1 



General Methods in Botanical Microtechnique. 



I. 



In the following account, I have attempted to give only such methods and 

 reagents as are required to carry on successful work and which I have found to 

 be the best in my own investigations. All details are carefully stated, so that a 

 beginner should be able, with little outside help, to carry the operations through 

 successfully. The methods employed in preparing plant tissues must be consid- 

 erably different from those used in zodlogy, since we usually have to deal with a 

 thick cellulose wall and a very delicate protoplasm in which are usually contained 

 large vacuoles filled with cell sap, besides numerous plastids and food contents, 

 all of which tend to make it difficult to preserve and study the finer details of 

 structure in plant cells and tissues. 



The objects taken for a trial study may be some root tips of the common 

 onion {AUiiini Cepa), or pieces of the young ovularies of some species of lily, as 

 Lilium Longifiorum or L. Philadelphicuin. The root tips may be grown by plac- 

 ing an onion in a flower pot with moist sawdust, and keeping it for a few days 

 where the roots will grow rapidly. The tips should be cut from one-half to three- 

 fourths of a centimeter in length. The lily ovularies may be taken at various 

 stages before and after the flowers open, and cut into transverse pieces from one- 

 fourth to three-fourths of a centimeter long. 



1.— KILLING AND FIXING. 



The first thing to do in beginning to prepare any plant tissue for permanent 

 mounting is to kill and fix it in such a way that it will preserve the minute struc- 

 tures as near the living condition as possible. A sharp knife or scalpel should 

 always be used, and great care taken so as not to bruise or injure any of the 

 cells. 



Killing F/iiid.—The. killing fluid is made up as follows : 



1. Chromic Acid - -. - - O.S cc. 



2. Glacial Acetic Acid - - - 0.5 cc. 



3. Water 90.0 cc. 



Have the killing fluid in a 4 oz. (1-20 cc.) bottle with a common cork. Sixty cubic 

 centimeters (2 oz.) of the fluid will be enough to kill one or two dozen objects the 

 size of the root tips. The material must be perfectly fresh and put into the killing 



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