DICOTYLEDONES 



453 



have actinoraorphic flowers, which often have the petals convolute in the bud. 

 In the more specialized types, such as the Labiatse (Fig. 443), Scrophnlariaceae 

 (Fig. 444), and Bignoniace* (Fig. 444, A), the flowers are markedly zygomor- 

 phic, and the number of stamens is reduced to four or two. Sometimes, as in 

 Verbascum (Fig. 444, D) and Fentsiemon, a more or less developed fifth stamen 

 is present. 



Most of the Tubiflorse are herbaceous plants, but there are woody plants 

 among them, sometimes trees (Catalpa, Paulownia), sometimes woody climbers 

 (Bignonia, Tecoma). 



Two families are especially well developed in the western United States, viz. : 

 Polemoniacese and Hydrophyllacese. To the first belong many beautiful species 



FIG. 443. A-F, Lamium aibum. G-I, Solanum dulcamara. J, Petunia sp. 



of Phlox and Gilia, to the latter the characteristic genera, Nemophila, Phacelia, 

 and Hydrophyllum (Fig. 442, D). 



Belonging to the Tubiflorae is the very peculiar family Lentibulariacese, repre- 

 sented by Utricularia and Pinguicula, characteristic carnivorous plants. Para- 

 sitic forms are not uncommon, e.g. Orobanche, Cuscuta. 



Order VI. Plantaginales 



The order Plantaginales contains a single family, Plantaginacese. The flowers 

 are inconspicuous, actinomorphic, and may be either hermaphrodite or diclinous. 



