BOTANY 



less replaced by irregular florets. Anacyclus ojficinarum. Matricaiia Chamomilla 

 (Chamomile, Figs. 781 b, 787) is an annual copiously-branched herb with a hollow, 

 conical, common receptacle, yellow disc-florets and white, recurved, female ray- 

 florets, in the terminal capitula. Chrysanthemum, C. segctum. Tanacetum, flowers 

 all tubular, marginal florets female. Artemisia has all the florets tubular and 

 usually the peripheral ones female (A. Absinthium, Wormwood) ; in the few- 

 flowered capitula of A. Cina (Fig. 788) all the florets are hermaphrodite. 



Tussilago Farfara, Coltsfoot, flowers appear before the leaves ; the flowering 

 stem bears scaly leaves and a single capitulum (Fig, 789) ; the flowers stand 

 on a smooth receptacle and have a fine white hairy pappus. Female flowers at 

 periphery in several series. Leaves large, cordate, thick, covered beneath with 

 white hairs. Petasites ojficinalis, Butter-Bur. Svnecio, plants of diverse habit, 

 including some trees and succulent plants ; of world-wide distribution. S. vul- 

 garis has no ray-florets but only tubular hermaphrodite florets. Doronicum, 

 Cineraria are commonly cultivated. Arnica montana (Figs. 780, 782, 790) has 

 a rosette of radical leaves in two to four opposite pairs and a terminal inflores- 

 cence bearing a single capitulum ; from the axillary buds of the two opposite 

 bracts one (rarely more) lateral inflorescence develops. Calendula and Dimorpho- 

 theca have the fruits of the capitulum of varied and irregular shapes. 



OFFICIAL. Anacyclus Pyrethrum yields PYRETHRI RADIX. SANTONINUM is 

 prepared from Artemisia maritima, var. Stechmanniana. Anthemis nobilis yields 

 ANTHEMEDIS FLORES. Taraxacum officinale, TARAXACI RADIX. Arnica montana, 

 ARNICAE RHIZOMA. Grindelia camporum. 



SUB-CLASS II 

 Monoeotylae 



The Monocotyledons, or Angiosperms which possess a single 

 cotyledon, are in general habit mostly herbaceous, less frequently 

 shrubs or trees. 



In germination the radicle and hypocotyl of the small embryo 

 emerge from the seed coat, while the sheath-like cotyledon usually 

 remains with its upper end within the seed and absorbs the materials 

 stored in the endosperm, which is usually well developed. The 

 growth of the main root is sooner or later arrested and its place 

 taken by numerous adventitious roots springing from the stem. In 

 the Grasses these are already present in the embryo within the 

 seed. Thus a single root system derived by the branching of a 

 main root, such as the Gymnosperms arid Dicotyledons possess, is 

 wanting throughout the Monocotyledons. 



The growing point of the stem remains for a longer or shorter 

 time enclosed by the sheath of the cotyledon. Later it bears in 

 two -ranked or alternate arrangement the leaves, which have long 

 sheaths and continue to grow for a considerable time at their bases. 

 The growth of the stem is often limited ; branching is in many cases 

 entirely wanting, and rarely results in the development of a highly 

 branched shoot-system. The leaves are mostly sessile and parallel- 

 veined, and of a narrow, elongated, linear, or elliptical shape 



