RADIX BELLADONNA. BELLADONNA ROOT. 97 



periphery and those nearer the endodermis being usually 

 the smaller. These cells are uniformly rich in starch. 

 A number of them contain crystals. 



The hairs of the root of sarsaparilla, while not a con- 

 spicuous part of the powder, yet afford a microscopical 

 character of much diagnostic importance. They are 

 short, irregular hairs with thin brown walls ; the general 

 length is about 150 to 200 microns, and their average 

 diameter about 20 microns. 



The cells of the endodermis are characteristic, yet in 

 some powders can be differentiated from some of the 

 hypoderm cells only with difficulty. They are thick- 

 walled, richly pitted, and sometimes contain starch grains. 

 Their average diameter is about 20 to 25 microns, and 

 they are usually three to four times as long as broad. 

 The vessels are of the spiral, reticulated, scalariform, and 

 pored types, the pores being both simple and bordered. 

 The diameter of the various ducts ranges from 75 to 250 

 microns, the largest ones being found near the centre. 



Tracheids and cells transitional between tracheids and 

 fibres are common. They range in diameter from 20 to 

 30 microns. The fibres are present in numbers; they 

 usually average about 20 to 25 microns in diameter, and 

 are not infrequently 200 microns long. Some of the 

 delicate-walled prosenchymatic elements, belonging to 

 the sieve elements, may also be found. 



Chemistry. — The chief constituents of sarsaparilla are 

 parillin, by some considered the active principle ; saponin, 

 I to 3 per cent.; resin, of bitter, acrid taste; starch, 

 3 to 45 per cent. ; crystals of calcium oxalate and traces 

 of a volatile oil. The ash constitutes 3 to 12 per cent. 



RADIX BELLADONNiE. BELLADONNA ROOT. 

 Belladonna Root is the root of Atropa Belladonna (nat. 

 order Solanaceco). Habitat, Central and Southern 

 Europe, in woods. 

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