124 POWDERED VEGETABLE DRUGS 



Sclerenchyma cells present. 



Abundant mature pollen grains. . (expanded) Pyrethrum flores 



Abundant immature pollen grains (unexpanded) Pyrethrum flores 



Fibrous tissue excessive, pollen grains few (stems) Pyrethrum 



Tapering pointed toward one end 



With glandular trichomes 



Pollen grains few Cusso 



Pollen grains abundant. (Papillae of stigma) Matricaria 



Glandular trichomes wanting 



Trichomes thick-walled Scoparius 



Trichomes thin-walled Lobelia 



Trichomes simple, 2- to 5-celled 



Glandular trichomes present 



' Sessile, many-celled 



Pollen grains spherical (conical projections) ...... Grindelias 



Pollen grains oval Scutellaria 



Sessile, single-celled Eupatorium 



Short-stalked. Tanacetum 



Glandular trichomes wanting 



Pollen grains with distinct conical projections 



Yellow coloring particles Calendula 



No yellow coloring particles (flowers) Arnica 



Pappus present 



Yellow glands Eupatorium 



No yellow color or glands (flowers) Arnica 



Trichomes wanting 



Pollen grains elliptical to oval Chirata 



Pollen grains triangular Caryophyllus 



.... Pollen grains few or wanting 



Trichomes wanting or few 



Sclerenchyma cells present 



Stomata present 



Guard cells indistinct. Cuticle very thick Eucalyptus 



Guard cells distinct Sabina 



Stomata wanting or very few 



Palisade tissue present Areca 



Palisade tissue wanting Pepo 



. Sclerenchyma cells wanting 



Stomata few or wanting 



Hypoderm present. Palisade tissue 



Starch present Pea and bean 



Starch wanting 



Palisade tissue with granular contents Fenugreek 



Palisade without granular contents 



Brown hypoderm Brassica nigra 



Nearly colorless hypoderm Sinapis alba 



Stomata abundantly present 



Vertical walls of epidermal cells sinuous 



Cuticle thick Chimaphila 



Cuticle very thin Lactuca 



