224 



PLANT ORGANS OR PARTS OF PLANTS. 



brown zone surrounds a lighter brown central zone. 

 Sections in the upper portion, just beneath the spreading 

 of the calyx lobes, cut into the ovary with its two carpels 

 and numerous ovules (about twenty) arranged on a cen- 

 tral placenta. The minute anatomy of the cross-section 

 shows greatly thickened outside epidermic cells, 13 to 15 

 microns in diameter; as Tschirch has pointed out, this is 



Fig. 62. — Clove. 



Cross-section of base of clove: e, Epidermis; /'^ parenchyma with 

 oil canals; Q) — /^^ parenchyma with interspersed vessel bundles; p^, 

 loose parenchyma; c, columella; g, vessels; i, oil cells (Wiesner). 



not strongly cutinized. Beneath this single epidermal 

 row there are numerous thin-walled parenchyma tic cells. 

 These are radially elongated, and surround numerous 

 schizogenous oil glands, which are arranged in from two to 

 three rows. The parenchymatic cells measure from 15 

 to 30 microns. The oil glands are oval elliptical, sur- 

 rounded by two or three rows of flattened secreting cells, 

 and measure from 170 to 220 microns in the radial diam- 



