746 BOTANY AND PHARMACOGNOSY. 



y3 Sclerenchymatic Tissue Wanting. 



I. Pollen Grains Numerous. 



8i. ARNICA FLORES.— Yellowish-brown ; pollen grains 

 spherical, with numerous centrifugal projections, 3-pored, 25 to 35 

 II. in diameter; non-glandular hairs of three kinds — either uni- 

 cellular, 5- or 6-celled or consisting of a pair of united unicellular 

 hairs with numerous pores on the dividing wall; glandular hairs 

 of three kinds — either with a large unicellular stalk and unicellular 

 glandular head, or with a stalk of a single row of 4 cells and a 

 I -celled glandular head, or a stalk of a double row of 5 cells and 

 a 2-celled glandular head; pappus consisting of a multicellular 

 axis with unicellular branches (Figs. 119, B ; 241). 



82. SAMBUCUS. — Starch grains not present; pollen grains 

 numerous, spherical or elliptical and nearly smooth, about 18 n 

 in diameter ; numerous fragments composed of broken or whole 

 anthers; corolla with dentate papillae; oil globules from secretion 

 cells; in calyx some rosette aggregates of calcium oxalate; in 

 flower stalk, large spiral duct 30 /^ wide, and parenchyma with 

 brown contents. 



83. MATRICARIA. — Pollen grains numerous, nearly spher- 

 ical or triangular, very spinose, from 18 to 25 jx. in diameter; 

 fragments of corolla with glandular hairs; characteristic cells of 

 anther; stigma with papillae; peculiar ladder-like cells of wall 

 of akene; sclerenchyma fibers of involucral scales. 



2. Pollen Grains Few. 



84. CALENDULA.— Bright yellow (Fig. 296, B) ; charac- 

 teristic tissue of petals containing oily drops ; few pollen grains ; 

 colored brownish with sulphuric acid. 



85. CROCUS.— Orange-red (Fig. 296, A) ; glycerin mount 

 of deep orange color ; few, nearly smooth, nearly spherical pollen 

 grains, 85 to 100 /^ in diameter ; papillae of stigma ; coloring prin- 

 ciple soluble in water but not in fatty oils, being the reverse in 

 capsicum ; with sulphuric acid fragments become blue immediately. 



86. ANTHEMIS.— Non-glandular and glandular hairs; 

 spherical, prickly pollen grains about 30 /u, in diameter, which are 



