POWDERED DRUGS 713 



This can be accomplished by treating the powder with chloroform, 

 xylol, acetone, ether, or other similar solvents. Alcohol as a rule 

 is not a good solvent for these oils. The solvent may be added 

 directly to the mount and the solution absorbed by means of filter 

 paper. The following drugs and foods contain fixed oil and should 

 be treated in this way: Almond, anisum, cacao, cardamom, carum, 

 conium, coriandrum, cubeba, ergota, linum, macis, myristica, pimenta, 

 pepo, piper, sinapis alba, sinapis nigra, staphisagria, strophanthus, 

 and the various cereal products. 



All powders contain a certain amount of fragments of cell walls 

 and other materials which are more or less alike in the different 

 powders, and it is important that this fact be borne in mind in order 

 that attention may be especially directed to those elements of the 

 powder which have a diagnostic value. The latter, while relatively 

 few in number, are easily identified and the distinguishing features 

 readily determined in nearly all cases. 



KEY FOR THE STUDY OF POWDERS 



POWDERS OF A GREENISH COLOR 



I Crystals of Calcium Oxalate present. 



A. CRYSTALS IN ROSETTE AGGREGATES. 



a. Glandular and non glandular hairs present. 



Cystoliths of calcium carbonate 1. Cannabis Indica 



Twisted non-glandular hairs 2. Eriodictyon 



Starch grains 15 to 40 n in diameter 3. Galla 



Large multicellular glandular hairs 4. Humulus 



Numerous pollen grains 5. Insect Powder 



Glandular hairs few 6. Stramonii Folia 



6. Glandular hairs wanting. 



Hairs with slight projections 7. Pilocarpus 



Characteristic stone cells 8. Tea 



C. Glandular and non-glandular hairs wanting. 



Sphere-crystals of a carbohydrate 9. Buchu 



Crystals 1 to 2 p in protein grains 10. Conium 



Crystals 15 ^ 11. Castanea 



Crystals 40 to 60 M 12. Chimaphila 



Outer wall of epidermal cells very thick 13. Eucalyptus 



Crystal fibers 14. -Granatum 



B. IN MONOCLINIC PRISMS. 



a. Glandular and non-glandular hairs present. 



Crystals about 10 M 15. Hyoscyamus 



