126 



filled witli st;irch .iiraiiis, which are commonly spherical, or unitefl iu 

 groups of two or three grains. Ilonrturas sarsaparilla. Smilax (ilHciuale, is 

 cliaraoterized by starcli grains vai-yiiig from 7 to 20 microns in diameter, 

 and raphides crystals (i to s micmns in length. The connn n P,and)oo 

 Brier root sliows similar characteristics when examined in fine powder. 

 but shows a variation in the starcli grain. Tlie starch grains (►f tliis drug 

 greatly resemble those of Honduras sarsaparilla. being either single or 

 united in groups, and sliow a similar structure in the interior of the grain : 

 but upon measurement they range in size from !) to 40 nuorons. averaging; 

 2i> microns in diameter. Hence, this means may be used in tlie differ- 

 entiation of these plants wlxen the drug is examined as a fine powder. 



By the application, of tlie above or of similar methods, it is possilile 

 to diflerenliate between very closely related plants. As our knowledgo 

 of the structure of starch grains is more fully developed, their value in the 

 differentiation of such closely related species becomes apparent, and they 

 are recognized as one of the greatest aids in I'harmacognosy. 



DcpariiiK'iit iif fUthnni. 

 Eli Jj'lUi d- ('(/iinxnii/. 



