THE JOURNAL OF PHARMACOLOGY. 213 



only a trace of true tannin was found, and no saponin. The aqueous ex- 

 tract is, however, in process of more minute examination ; the outcome 

 will be reported shortly. 



The results of the above analysis may be summarized as follows : 



Per cent. 



Moisture, 5- 2 5 



Fatty matter, including chlorophyll, 7.34 



Acrid resin soluble in benzin, 9.80 



Coloring-matter soluble in ether and water 0.20 



Grindeline (?), a trace 



Resin insoluble in benzin, 7°° 



Volatile oil, caoutchouc, 0.26 



Tannin like coloring- matter, 



Tannin, '• & trace 



These results, compared with those of Clark and Fischer, make it highly 

 probable that grindelia is very variable in its chemical constituents. This 

 opinion is consistent with the behavior of the drug in medical practice. 

 Dr. William MurrELL* cites it as an example of the extreme uncer- 

 tainty of some drugs. Regarding the relative efficiency of the alcoholic 

 and the alkaline aqueous extracts, it is a question whether the glucoside, 

 grindelin, of Clark, or the acrid resin above described, is the active princi- 

 ple. This problem is beyond the field of the writer ; but as soon as he can 

 obtain some of the grindelin, if it is obtainable, he will place it and the 

 acrid resin in the hands of those who are competent to determine this 

 point. During the coming year a series of examinations will be made of 

 plants collected at various stages of their growth and kept for various 

 lengths of time. Should he be able to determine under what conditions 

 the drug is efficient, and when not so, thus rendering constant a drug at 

 present uncertain, the writer will feel himself well rewarded for his labors. 



In conclusion the writer desires to express his thanks for much valuable 

 advice given him by Professors Rusby, Coblentz, Diekman and Jelliffe 

 during his work. — Merck's Report. 



EXPLANATION OF FIGURES. 



(Referring to the figures published in Vol. V., No. 8, but inadvertently omitted.) 

 Fig. i.— Cross-section of the stem of Grindelia robusta, magnified 16 diameters. 

 Fig. 2. -Segment of a cross-section of the stem of Grindelia robusta, magnified 175 



diameters. E, epidermis ; P, parenchyma ; B, bast fibers ; C, cambium layer ; V, 



vessels ; T, tracheids. 

 Fig. 3.— Radial longitudinal section of the stem of Grindelia robusta, magnified 165 



diameters. P, parenchyma ; B, bast fibers ; F, libriform fibers ; T, tracheids. 

 FiG. 4.— Powder of Grindelia robusta, magnified 165 diameters. A, tip of an awn ; B, 



bast fibers ; C, portions of corolla lobes ; E, epidermis of stem ; F, fat globules ; G, 



resin gland on leaf; L E, leaf epidermis with stomata ; M, inner portion of achene; 



P, pollen grains ; R, fragments of resin ; S, stone cells from achene ; T, tracheids ; 



S P, parenchyma from stem ; S C, seed coat ; S V, spiral vessel ; W, wood fibers. 



* Pharmacology and Therapeutics, Merck's Report, 1896. 



