252 



BOTANY FOR BEGINNERS 



CHAP. 



ivum\ and the White Mustard (B. alba) are used for salads, (c) For 

 their inflorescences Cauliflower and Broccoli are varieties of Cabbage. 

 Their inflorescences are branched and very succulent. The flowers are 

 very minute, (d] For their seeds, Black Mustard (B. nigra), from 

 which the mustard of commerce is produced, (e) For their oil, Rape 

 and Colza (varieties of Brassica}. The oil is obtained from their seeds. 



Natural Order: Carophyllese, (Stitchwort family). 

 The plants belonging to this order have swollen nodes, opposite 

 leaves which are entire and narrow. The flowers are solitary or in 

 dichotomous cymes. The calyx consists of five united or free 

 sepals. The corolla is made up of five petals, each deeply cut 

 or entire. There are 10 stamens in two series which ripen five 

 at a time. The pistil is syncarpous, the 

 carpels varying in number from 3 to 5. 

 The placentation of the ovules is axile. 

 Fruit is a capsule. The flowers are pro- 

 tandrous and pollinated by insects. 



NOTE. No other order possesses the 

 combined characters of swollen nodes, oppo- 

 site entire leaves, and 10 free stamens in two 

 series. 



Floral formula. K$,C5,A$ + 5,6(2 to 5) 

 Description of a typical Caryo- 

 phyllaceous Plant (Stellaria media). 

 $titchwort. 



Habit. An annual herbaceous plant with many branches, 

 which grows nearly everywhere. 

 Root. Short, and very slender. 



Stem. Swollen at the nodes, very hairy, herbaceous and 

 green. 



Leaves. Cauline, opposite, simple, entire, narrow. Lower 

 leaves possess petioles, while the upper are sessile ; exstipulate. 

 Inflorescence. Definite, forming dichotomous cymes. 

 Flowers. Complete, actinomorphic, stellate, small, white. 

 Calyx. Polysepalous ; 5 inferior green sepals. 

 Corolla. Polypetalous ; 5, hypogynous, petals split. 

 Andrcecium. Free ; 10 stamens in two series ; hypogynous ; 

 the outer whorl of stamens is opposite the petals, and the others 

 alternate with them ; filament slender ; anther two-lobed. 



Gyncecium. Syncarpous ; carpels 3 ; superior ; styles 3 ; 

 stigmas 3. 



FIG. 244. Floral 

 diagram. 



