108 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



whorl at the summit, and subtending the large sessile dark purple 

 flowers which have an unpleasant odor and for this reason the plant 

 is called " ill-scented Wake-robin." 



Description. Rhizome upright or horizontal, obconical or some- 

 what cylindrical and compressed from above; from 2 to 6 cm. in 

 length and 0.75 to nearly 3 cm. in diameter; externally yellowish- 

 to reddish-brown, distinctly annulate from scars of bud scales, the 

 summit being terminated by a small bud, and the upper surface of 

 the oblique rhizomes marked by a few scars of ascending branches, 

 in addition the outer surface is marked by numerous circular root 

 scars or has attached the long fibrous roots ; fracture short, somewhat 

 uneven and mealy; the fractured surface being yellowish-white or 

 light brown, mealy, and with a waxy luster; odor distinct; taste 

 starchy, bitter and acrid. 



Inner Structure. Epidermal layer of somewhat tabular cells 

 with very thick reddish-brown porous walls; the hypodermal layer 

 consisting of tangentially elongated cells, the outer layers of which 

 have reddish-brown thick walls; the remainder of the rhizome con- 

 sists of large thin-walled starch-bearing parenchyma, interspersed 

 among which are the lepto-centric vascular bundles and cells con- 

 taining raphides of calcium oxalate; starch grains mostly single, 

 nearly spheroidal, having a distinct central cleft and varying in size 

 from 0.003 to 0.020 mm. in diameter, occasionally more or less altered 

 and swollen starch grains from 0.020 to 0.030 mm. in diameter; 

 acicular crystals of calcium oxalate from 0.015 to 0.060 mm. in length; 

 tracheae about 0.025 mm. in width and with spiral or reticulate thick- 

 enings. 



Constituents. Saponin (trilline), 4.86 per cent; a resinous sub- 

 stance; considerable starch; a small quantity of volatile oil; ash, 

 4 to 5 per cent. 



ORNITHOGALTJM THYRSOIDES. A bulbous plant (Fam. Liliaceae), 

 which is common in Cape Colony. Chemical examination of the 

 entire flowering plant, including the underground, bulbous portion, 

 shows the toxic principle to be chiefly contained in the resin. 

 Attempts to obtain a definite active principle have been unsuc- 

 cessful. Power, Pharm. Journ., 1910, p. 32. 



DIOSCOREACE^E, OR YAM FAMILY 



These are mostly twining plants with large tuberous roots or 

 knotted root stocks. There are about 175 species most of which are 

 indigenous to the West Indies and South America. The anatomy of 



