SANTONICA. LEVANT WORMSEED. 211 



first an arc of two rows of sclerenchymatic cells which 

 form the keel, and within a body mass of chlorophyll 

 containing parenchyma, through which runs a small 

 central fibro-vascular bundle of concentric structure, the 

 central vessel portion of spiral-annular ducts surrounded 

 by smaller thinner wall liber and the whole enclosed in 

 distinct endodermis. There is usually present a secre- 

 tory canal smaller than the fibro-vascular bundle. On 

 either side of the keel is a row of large, several celled 

 oil glands. These are similar in structure to those of 

 the Labiates. They are more numerous in the true than 

 in other varieties of the drug. In the neighborhood of 

 these glands are found organic crystals soluble in ether. 

 Calcium oxalate needles are also present. The flower 

 tissue, consisting principally of corolla, bears many 

 similar glands situated in depressions in the lobe. Within 

 the thick-walled epidermis of the corolla lobe are two 

 rows of palisade cells. Within run several minute fibro- 

 vascular bundles. 



Powder. — The elements of the powder are numerous, 

 the most frequent being three-sided, almost globular 

 pollen grains. Glands from the bracts and floral leaves 

 are frequent. Long, irregular, pointed stone cells from 

 the keels of the involucre scales, fibres, annular ducts, 

 and parenchyma from the fibro-vascular bundles, por- 

 tions of pitted walled epidermis with many stomata and 

 irregular cubical organic crystals make up the rest of 

 the powder. 



Chemistry. — The active principle of Santonica is san- 

 tonin, 1.5 to 2 per cent., in colorless prismatic crystals, 

 turning yellow in the light. They are slightly bitter, 

 almost insoluble in water, dissolve in alcohol and ether, 

 and form crystal lizable salt with alkalies. Three per 

 cent, of a thin, yellow, unpleasant smelling volatile oil, 

 boiling at 170°?., resin, etc., are also present. 



