sect, n 



PHANEROGAMIA 



475 



plant growing in bogs and swampy places, the spathe is white on the upper 

 surface and envelops a spadix completely beset with hermaphrodite flowers. 



Officinal. — From Acorus Calamus, Sweet Flag (Fig. 414), a marsh plant with 

 creeping rhizome, narrow leaves, and greenish inflores- 

 «l cences of hermaphrodite flowers, Rhizoma Calami is 



obtained. 



Family Lemnaeeae. — Greatly reduced Ara- 

 ceae. Flowers monoecious, naked ; the male 

 consisting merely of one stamen ; the female, 

 similarly, of a single carpel. Inflorescence, a 



Fig. il6.—Wolffia (irrMsn. (After Hegelmaier, X10.) 



spadix formed of three flowers, two male and 

 one female, invested with a spathe. Small, FREE- 



SWIMMING, DISC-LIKE, LEAFLESS WATER-PLANTS 



(Figs. 415, 416). 



Fig. 415. — Lemna 



Flower ; //■, fruit ; w, root ; 

 -ict, root - pocket. (After 

 Hegelmaier, magnified.) 



The green vegetative body of the Duckweed has usually 

 been regarded as a system of naked leaf-like axes ; more 

 recently it has been asserted that it consists essentially 

 of leaves. 

 Geneka. — Spirodela, Lemna, Wolffia (without roots). 



Geographical Distribution. — Duckweed is found everywhere in quiet or 

 stagnant water. 



The following families are also included in the order Spadiciflorae : — Paiidanaccac. 

 Tropical trees borne on stilt-like roots ; leaves sword-shaped, inflorescence a large 

 spadix. Cyclantliaceae ; tropical lianes and shrubs, often resembling Palms but 

 bearing many -seeded berries. Sparganiaceae and TypJiaceae ; grass -like marsh- 

 plants, the latter possessing thick brown cylindrical inflorescences. Sparganium and 

 Typha are represented in Germany. 



Order 4. Glumiflorae 



Flowers hypogynous, hermaphrodite or unisexual, NAKED OR 

 WITH REDUCED PERIGONE ; ovary unilocular, containing one ovule ; 

 inflorescence with many small flowers, and numerous glumaceous 

 bracts. For the most part herbs with linear parallel-nerved 

 leaves. 



All the Glumiflorae have a grass-like appearance, i.e. they are 

 herbaceous, rarely woody plants, with narrow pointed leaves, and have 

 inconspicuous inflorescences bearing small flowers and numerous scale- 

 like bracts. The bracts are dry, green or brownish hypsophylls, 

 in part sterile and to some extent serving as subtending leaves 



