516 MANUAL OF NATURAL HISTORY. 



or indefinite, hypogynous ; anthers sessile, 1- 

 2- or many-celled, extrorse ; ovary free, most- 

 ly 1 -celled ; stigma sessile ; fruit succulent ; 

 seeds pulpy ; embryo slit, axile. Inhabitants 

 principally of hot countries. Many are poi- 

 sonous ; the corms of some abound in amyla- 

 ceous matter. (Aroidece, Juss.) 



3. Family. — Bulrushes (Typhacese). Herbaceous ; 

 stems nodeless; leaves rigid, ensiform; flowers 

 upon a spatheless spadix ; perianth scaly or 

 hairy ; stamens 3-6 ; anthers wedge-shaped, 

 on long filaments, which are sometimes mona- 

 delphous ; ovary superior, 1 -celled ; ovule 

 solitary ; style short ; stigma linear ; fruit 

 dry, 1 -celled, 1 -seeded ; seed adherent to its 

 pericarp ; embryo slit. Occur in ditches and 

 marshes in northern countries. 



4 Family. — Duck-weeds (Pistiaceae). Herbaceous ; 

 leaves very cellular ; flowers 2-3, enclosed in 

 a spathe, without a spadix ; stamens definite, 

 often monadelphous ; ovary 1 -celled ; style 

 short ; stigma simple ; ovules two or more, 

 erect ; fruit membranous or capsular : embryo 

 slit. Found in ditches in temperate parts of 

 the world. 



III. SUB-CLASS. — Scale-flowered Endogens 

 (Glumalese). 



Flower glumaceous, i. e , consisting of imbricated, 

 colourless herbaceous scales or bracts. 



