CALENDULA 77 



Substitutes, &C. From time to time a variety of wormseed 

 containing little or no santonin appears on the market ; it may be 

 recognised by the more or less hairy nature of the bracts. 



Use. Wormseed is now seldom administered, but santonin is often 

 employed as an anthelmintic for round worms which it rapidly expels ; 

 it has less effect upon thread-worms and no action on tape worms. 

 It produces remarkable disturbances of vision, objects appearing first 

 blue and then yellow, and the absorbed santonin renders the urine 

 intensely yellow if acid or purplish if alkaline. 



Certain other species of Artemisia (e.g. A. gallica, Willdenow) have 

 anthelmintic properties. American wormseed (A. anthelmintica) is 

 cultivated in California. 



CALENDULA 



(Flores Calendulas, Marigold Florets) 



Source, &c. The marigold, Calendula officinalis, Linne (N.O. 

 Composite) , is commonly cultivated in numerous varieties as a garden 

 plant. The flower head is about 5 cm. in diameter, yellow to deep 

 reddish orange in colour, with numerous barren disc-florets and one 

 or more rows of fertile ligulate ray-florets. The latter are collected 

 when the flower is fully expanded and dried. 



Description. The drug consists almost entirely of the ligulate 

 corollas of the ray-florets, about 2-5 cm. in length, enclosing in a 

 short tube the remains of the style and two stigmas. The limb of the 

 corolla, the tube of which is hairy externally, is terminated by three 

 teeth, and exhibits, when examined with a lens, four principal veins. 

 (Compare fig. 47 B.) 



The drug has a somewhat aromatic odour and a distinctly bitter 

 taste. 



The student should soften some calendula in water, spread the 

 florets out, and examine them with a lens, noting 



(a) The three teeth of the corolla, 



(b) The four principal veins ; 



and should compare them with the ligulate florets of arnica (which 

 have about seven to nine veins) and of dandelion (which have five 

 teeth). (Compare figs. 44 A, and 47 B.) 



Constituents. Calendula contains traces of volatile oil, a bitter 

 principle, and calendulin, the latter being a tasteless substance swelling 

 in water (Geiger, 1818). 



Uses. Calendula is used chiefly in the form of the tincture diluted 

 with water as an application to bruises to promote the absorption of 

 effused blood. 



