42 MISCELLANEOUS PAPEES. 



the true from the false pinkroot, as it is now definitel}^ known that 

 certain of the trade varieties are wholly composed of worthless sub- 

 stitutes. 



In many cases careless or unscrupulous collectors and dealers have 

 not regarded the distinguishing features of the various sorts of pink- 

 root, or have been ignorant of them, with the result that very general 

 confusion exists as to the character of the real drug and its adulter- 

 ants. The authors of some prominent publications on crude drugs 

 have evidently based their observations on trade varieties of pinkroot, 

 as they have illustrated and described one of the most important adulter- 

 ants as true pinkroot. 



IDENTITY OF CHIEF SUBSTITUTES. 



East Tennessee pinkroot {Ruellia ciliosa Pursh), a member of the 

 plant family Acanthaceae, is the most important adulterant. Observa- 

 tions on the plant structures present in commercial samples of pinkroot 

 convinced Dr. R. H. True, in 1900, that the chief part of this crude 

 drug consisted of a substitute instead of Spigelia and that this substi- 

 tute was a species of Ruellia. In trying to get plants of pinkroot for 

 cultivation. Doctor True, in 1903, purchased several hundred roots 

 from a dealer in eastern Tennessee. These roots were set out in the 

 testing gardens of the Bureau of Plant Industry at Washington, D. C, 

 and the plants kept under close observation. On developing they 

 were found to differ markedl}^ from 8pigelia, and upon flowering were 

 identified as Ruellia dlloxa (PI. VI), a plant which had never appeared 

 in the list of suspected adulterants prior to this time. 



The examination of the microscopic structure of this plant recalled 

 at once the tigures in some text-books purporting to represent Spige- 

 lia and those illustrating an article by Greenish in the Pharmaceutical 

 Journal, 1891, on the structure of Phlox Carolina, a plant which had 

 long been regarded as an extensive substitute for pinkroot. It was 

 evident that a double confusion existed with regard to Kiiellia. On 

 the one hand it was so widely mistaken for Spigelia that its peculiar 

 structures have been regarded as diagnostic of pinkroot, and on the 

 other it was recognized as a substitute, but wrongh^ regarded as Phlox, 

 a plant lacking many of the striking characteristics of Ruellia. 



In order to satisfactorily determine the relation of these substitu- 

 tions to the true pinkroot, observations have for three years been 

 made upon plants of Spigelia, Ruellia, and Phlox under cultivation at 

 Washington, D. C, and fresh material secured from them has been 

 use'^ in making a comparative study of their structure. The results 

 of this study do not support the view that Phl(5x is an adulterant of 

 pinkroot, and, moreover, several samples of a substitution supposed 

 to be Phlox have proved, upon examination, to be composed entirely 

 of Ruellia. It is only through long and familiar observation in the 



100— V 



