The Microscope. 133 



DESCRIPTION OP PLATE. 



Flax seed, x 2|-. 1 a, surface x 90. 

 Surface of diy seed, x 245. 



Surface of seed after soaking and drying, x 275. 

 Section testa and part of cotyledon, x 275. 

 Inner layer of testa, a, b, c, x245; d, e, x 275. 

 Section of testa, etc., of soaked seed, x 245. 

 Section of diy seed in water, etc., x 245. 

 Structure outer coat of testa, diagrammatic, x 275. 

 Spiral tissue, x 245. 

 Figure 10. Inner coat of testa, boiled in nitric acid, x 245. 



THE MOUNTING OF SERIAL SECTIONS. 



CHARLES SEDGWICK MINOT. 



L7 very one knows that the art of making and preserving long 

 -*-^ series of sections is one which has acquired the highest degree 

 of importance for various biological and particularly embryological 

 researches. It is, therefore, very important that the art should be 

 brought to as high a degree of perfection as possible. My own 

 work has rendered this very desirable for myself, and I have spent a 

 good deal of time in testing the various methods that have been 

 recommended. The result of these trials has been the selection now 

 from one authority and now from another of various methods of 

 treatment and manipulation, which as I now combine them in my 

 practice, yield me on the whole the best results which I have obtained 

 up to the present time. I have thought that it might interest others 

 and perhaps save them some time to have the results of my exper- 

 ience, together with mention of the special precautions which I have 

 found it advisable to take. 



First of all, I would state that it is my conviction that more 

 perfect and satisfactory series can be prepared with the aid of some 

 form of automatic microtome than by any of the older forms of 

 sledge or other microtomes with which we are familiar. It is 

 extremely difficult for the hand to acquire the steadiness and preci- 

 sion of movement possible with a mechanical appliance ; it is always 

 likely that a fine piece of apparatus working automatically will 

 prove a better instrument of precision than an apparatus worked by 

 the hand. Personally, I have found the automatic microtome made 

 by G. Baltzar of Leipsic, to be entirely satisfactory, and as it is not 

 expensive it seems to me, that it may be highly recommended.* 



* The microtome may now also be obtained from the Educational Supply Co., 6 Hamilton 

 Place, Boston, Mass. 



