126 



filled with starch grains, which are commonly spherical, or united in 

 groups of two or three grains. Honduras sarsaparilla, Smilax officinale, is 

 characterized by starch grains varying from 7 to 20 microns in diameter, 

 and raphides crystals G to S microns in length. The connnon Bumboo 

 Brier root shows similar characteristics when examined in fine powder, 

 hut shows a variation in the starch grain. The starch grains of this drug 

 greatly resemble those of Honduras sarsaparilla. being either single or 

 united in groups, and show a similar structure in the interior of the grain ; 

 but upon measurement they range in size from 9 to 40 microns, averaging 

 2t> microns in (liaiiietcr. Hence, this means may be used in the differ- 

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



By the application of the al>ove or of similar methods, it is possible 

 to differentiate between very closely related plants. As our knowledge 

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

 differentiation of such closely rehited species becomes apparent, and they 

 are recognized as one of the greatest aids in Pharmacognosy. 



Department of liottiiwj. 

 Eli Lilly d- Comixntii. 



