POWDERED DRUGS 717 



2. Pigment cells present. Continued. 



Short sclerenchymatous fibers 79. Linum 



A colorless layer of cells with minute starch grains. 



80. Cydonium 



Sclerenchymatous tissue wanting. 



1. Pollen grains numerous. 



Fragments of pappus 81. Arnica? Flores 



Pollen grains smooth 82. Sambucus 



Pollen grains spinose 83. Matricaria 



2. Pollen grains few. 



Pollen grains prickly 84. Calendula 



Pollen grains nearly smooth 85. Crocus 



Corolla white 86. Anthemis 



Bitter, ducts scalariform 87. Clara t a 



3. Pollen grains wanting. 



* Fibrovascular tissue present. 



Containing inulin masses : . . 88. Lappa 



Sclerenchymatous fibers numerous 89. Senega 



Starch and scalariform tracheae 90. Aspidium 



** Fibrovascular tissue wanting. 



Few fragments of tissues 91. Cambogia 



Large glandular hairs 92. Lupulinum 



Tetrahedral spores 93. Lycopodium 



Few or No Fragments of Vegetable Tissue. 



A. GIVING OFF ODOR OF SULPHUR DIOXIDE ON HEATING. 



Rounded masses in chains 94. Sulphur Lotum 



Rounded masses in irregular groups 95. Sulphur Praecipitatum 



B. No ODOR OF SULPHUR DIOXIDE ON HEATING. 



a. Nearly colorless in glycerin mount. 



Transparent, irregular masses 96. Mastiche 



6. Yellowish in glycerin mount. 

 a Containing oil globules. 



Irregular masses 97. Scammonium 



/3 Transparent or translucent. 



Soluble in cold alcohol 98. Colophony 



Insoluble in cold alcohol 99. Sandarac 



Reddish with alkalies 100. Aloe (Cape) 



7 More opaque. 



Light or grayish particles 101. Ammoniac 



Yellowish particles 102. Cambogia 



