CLASSIFICATION OF ANGIOSPERMS. 401 



folia), of South America, is poisonous to sheep and cattle and 

 contains an alkaloid, baccharine, and a bitter principle. Spiny 

 CLOTBUR (Xaiithiuiii spinosiiin) contains a bitter resin and possi- 

 bly a volatile alkaloid. The fruit of Xanthinm striimarium, a 

 common weed naturalized from Europe, contains an amorphous, 

 non-glucosidal substance, xanthostrumarin, which forms precip- 

 itates with a number of the alkaloidal reagents. Sneeze-weed 

 (Hclciiiuni aiituuinalc) contains a volatile oil, a bitter glucoside 

 and tannin. Heleniuin fciinifoliiiiii, of the Southern United States, 

 is a narcotic poison. Para cress {SpiUvithcs olcracca), of trop- 

 ical America, contains a soft pungent resin and a crystallizable 

 principle, spilanthin. The common white daisy (Chrysanthciuum 

 Lciicaiithcminii) yields about 0.15 per cent, of a greenish volatile 

 oil with the odor of chamomile and mint. 



Chicory, the root of Cichorinui Intyhiis, a perennial herb 

 with blue ligulate florets, indigenous to and cultivated in Europe 

 and naturalized in certain localities in the United States, is used 

 in medicine as well as in the preparation of a coffee substitute. 

 The root is spindle-shaped, somewhat resembling Taraxacum, but 

 is of a light brown color and the laticiferous vessels are arranged 

 in radial rows in the somewhat thinner bark. It contains a bitter 

 principle and a large amount of inulin. In the preparation of a 

 coffee substitute the root is cut into rather large, equal pieces and 

 roasted, after which it is ground to a yellowish-brown, coarse 

 powder. The grains are heavier than water, imparting to it a yel- 

 lowish-brown color. Under the microscope it is distinguished by 

 the branching latex-tubes and rather short, oblique tracheae with 

 rather large, simple pores. 



The Sunflower {Helianthus anuiiiis) is an annual herb indig- 

 enous to tropical America and extensively cultivated. The plant 

 is grown on a large scale in Russia, Hungary, Italy and India for 

 its fruits, which yield a fixed oil resembling that of cotton seed. 

 The akenes (so-called seeds) are obovate, flattened, externally 

 black or with alternate white and black stripes, the pappus con- 

 sisting of two deciduous, chaffy scales. Sunflower seed-cake is 

 readily distinguished by a few of the fragments of the epicarp, 

 with the characteristic twin, unicellular, non-glandular hairs and 

 large, oblique, but rather short, sclerenchymatous fibers. Besides 



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