266 THE AMERICAN MONTHLY [November, 



EOSINE. 



Eosine . . . . . . . . . o.^ gm. 



Absolute alcohol ....... 50 ccm. 



Glycerine 50 ccm. 



IODINE SOLUTION. 



Iodine ......... i gm. 



Potassium iodide ....... 3 gm. 



Distilled water ........ 60 ccm. 



Aniline sulphate is used to distinguish woody fibre from cellu- 

 lose, as are phloroglucine and eosine, while iodine is used to de- 

 tect starch. The solutions are to be kept in glass-stoppered drop- 

 bottles, and one drop dropped therefrom upon the edge between 

 the object-glass and cover-slip when used. Aniline sulphate 

 colors the woody fibre cells brownish-yellow, and leaves the cellu- 

 lose cells uncolored. Phloroglucine, the preferable one of the 

 three, colors the woody fibre cells a lovely pink and leaves the 

 cellulose uncolored. Iodine, of course, as we all know, colors 

 starch a deep purple-violet and does not color inulineor inorganic 

 salts. There are many other staining agents, but the above will 

 answer all purposes, and are usually preferred for botanical 

 microscopy. 



At first it will, of course, be necessary to watch and study the 

 plates very closely, making them answer the purpose of an in- 

 structor, but soon we will learn by experiences and actual obser- 

 vation the characteristics of most standard drugs, and then be able 

 to decide without reference to our plates. By following the 

 method outlined in this paper there is hardly any doubt that al- 

 most every one can recognize drugs microscopically, and with a 

 minimum expenditure of time and money. Besides the advan- 

 tage gained in determining the drug, there is a fascination in 

 microscopic work that will, I venture to assert, take hold of every 

 one who has any desire at all to enter into it, and repay him 

 amply in the shape of enjoyment, satisfaction, and pride. 



In order to facilitate the understanding of those who are unfa- 

 miliar with microscopic work, a brief description of the various 

 parts of the plants seen under the microscope may not be out of 

 place. It must be borne in mind that as a rule we have to deal 

 with roots and stems, but that sometimes we are also called upon 

 to examine pollen and fruit of plants, as, for instance, buchu, 

 kamala, and anise, respectively. 



For leaves and fruits, as for roots and stems, we usually take 

 only cross-sections for examination, while for pollen and exudates 

 we usually take the substance as it is met with in commerce. In 

 making a cross-section of a leaf it is well to make the same as 

 near as possible to the midrib, which is also to be included in the 

 section. The difference in the various drugs will be found to 

 consist largely, if not entirely, of the different arrangement of 



