CRUDE DRUGS. 639 



Description. — Stem quadrangular, i to 4 mm. in diameter, 

 varying in color from yellowish-green to purplish-red; mostly 

 glabrous below and hairy above. Leaves ovate, ovate-oblong-, or 

 ovate-lanceolate, opposite, 1.5 to 8 cm. long, 0.5 to 2.5 cm. broad; 

 apex acute or acuminate; base acute, rounded or sub-cordate; 

 margin coarsely serrate; upper surface dark green, glabrous; 

 under surface light green, nearly smooth, veins of the first order 

 diverging at an angle of 65", curving upward and anastomosing 

 near the margin ; petiole 2 to 10 mm. long. Flowers axillary and 

 solitary above or in i-sided racemes ; calyx campanulate, toothed, 

 about 2 mm. long; corolla white or blue, about 6 mm. long, the 

 limb 2-lipped ; stamens 4, didynamous, hairy, the anthers of the 

 upper pair with 2 pollen sacs, the lower with one ; style unequally 

 2-cleft and ovary deeply 4-parted. Fruit consisting of 4 ellip- 

 soidal, distinctly tuberculate, light brown nutlets about i mm. 

 long, borne on an enlarged torus known as the gynobase, and 

 enclosed by the persistent bilabiate calyx, the upper part of which 

 becomes helmet-shaped after fertilization, whence the name 

 " Skullcap." Odor slight. Taste bitter. 



Constituents. — A bitter crystalline glucoside scutellarin; a 

 small quantity of volatile oil, of which little is known. 



Allied Plants. — Several species of Scutellaria growing in 

 the United States are sometimes substituted for the official drug, 

 nearly all of which have the flowers in terminal panicled racemes. 

 Heart-leaved skullcap (Scutellaria cordifolia) is densely gland- 

 ular pubescent, even the corolla being hairy ; Hairy skullcap {S. 

 pilosa) is pubescent below, with numerous glandular hairs above, 

 and the corolla is nearly glabrous ; Hyssop skullcap (S. integri- 

 folia) has linear entire upper leaves.; in Marsh skullcap {S. 

 galericulata) the flowers occur in the axils of the nearly sessile, 

 narrow leaves. The European skullcap (S. altissima) has broad, 

 ovate, glabrous leaves and terminal panicles of blue flowers. 



Substitutes. — Scutellaria canescens, a plant growing, west 

 of the Mississippi, furnishes much of the drug on the market. 

 The plant is more robust than 5'. lateriflora; the leaves are oblong, 

 petiolate, 10 to 12 cm. long, 3 to 5 cm. broad, very hairy on the 

 tinder surface, with prominent veins, and crenate-dentate mar- 

 gin ; and the flowers are large, blue and in terminal racemes. 



