DICUTYLEDONES 



439 



Freinontia (Fig. 431), have no corolla, but the sepals in this case are petaloid. 

 The carpels are usually completely united, but in the Malvaceae the fruit is a 

 "schizocarp," and separates at maturity into as many parts as there are car- 

 pels. The stamens are usually numerous, and may be united into a tubular 

 column (Fig. 430). 



Most of the Malvales of temperate regions belong to the Mallow family 

 (Malvaceae). Examples are the various species of Mallow (Malva), Hollyhock 

 (Althea), and Hibiscus. H. moscheutos of the Eastern states is one of the 

 showiest of our native plants. 



The Bass-woods (Tilia sp.) (Fig. 430, F) represent the Tiliaceae, and the 

 Sterculiacese, for the most part a tropical family, has in California a single 

 representative, Fremontia Californica. 



B 



FIG. 433. Passijiora incarnata; t, tendril. B, section of the ovary. 



Order X. Parietales 



The order Parietales is a very large one, but the majority of the families 

 included are not represented within our territory. There is great variety in 

 the structure of the flowers, but most of them agree in having the ovules attached 

 to the wall of the ovary ; i.e. the placenta is " parietal." (Figs. 432, 433.) 



The most important families represented in the American flora are the 

 Theacese, Hypericacese, Cistacese, Violacese, Passifloracese, and Loasacese. 



To the Theacese belong the genera Stuartia and Gordonia, related to the 

 genus Camellia, one of whose species furnishes tea. The numerous species of St. 

 John's-wort (Hypericum) represent the Hypericacese. Helianthemum and sev- 

 eral cultivated species of Cistus are the most familiar examples of the Cistacese. 

 The Violets (Violacese) and Passion-flowers (Passifloracese) are represented by 

 numerous cultivated species, as well as by some native ones. 



The family Loasacese is a characteristic American one, mostly tropical, but 



