460 HYDROPHYLLACE^E CONVOLVULACE^. 



ance of a membrane. Pokmonium cceruleum, Greek Valerian, or Jacob's 

 ladder, is bitter. 



954. Order 130. iiydrophyiiace. the Hydrophyllum Family. 

 (Monopet. Hypog.) Calyx 5 -parted, persistent. Corolla monopetalous, 

 hypogynous, regular, 5-cleft; aestivation plicate or imbricate. Stamens 

 5, inserted upon the corolla, and alternate with its segments; filaments 

 sometimes petaloid ; anthers deeply-lobed at the base, often versatile, 

 2-celled, dehiscing longitudinally or transversely. Disk annular or 0. 

 Ovary free, 1-2-3-celled; ovules definite or indefinite; style 1 or 2 ; 

 stigmas usually 2. Fruit capsular, 2-valved, 1-2-celled, with a parie- 

 tal, or a large central placenta. Seeds with a brittle or reticulated 

 testa ; embryo in the midst of fleshy or cartilaginous albumen ; radicle 

 next the hilum. Trees, shrubs, or herbs, with opposite, or alternate, 

 exstipulate, often lobed leaves. They occur both in the northern and 

 southern parts of America chiefly. They have no properties of im- 

 portance. Many have showy flowers, and some have glandular or 

 stinging hairs. The order has been divided into two suborders : 



1. Hydrophylleae, including Hydrollese of authors, with the anthers 

 dehiscing longitudinally, disk present, ovary 1-2-celled, styles 2. 



2. Diapensiese, with anthers dehiscing transversely, disk 0, ovary 

 3-celled, style single. There are 18 known genera, and 77 species. 

 Examples Hydrophyllum, Hydrolea, Nemophila, Phacelia, Diapensia. 



955. Order 131. Convolrniacete, the Convolvulus or Bindweed 

 Family. (Monopet. Hypog.) Calyx in 5 divisions, persistent, imbricated, 

 often bracteated (figs. 652-654). Corolla monopetalous, hypogynous, 

 deciduous, regular; limb 5 -lobed, with a plaited or imbricated aestiva- 

 tion (fig. 653 />); tube sometimes with scales, alternate with the lobes 

 of the limb. Stamens 5, inserted in the base of the corolla, and alter- 

 nate with its lobes (fig. 654 e). Disk annular, hypogynous. Ovary 

 free, 2-4-celled, rarely by abortion 1 -celled; ovules definite, erect, 

 when more than one, collateral ; style 1 (fig. 654 s), usually bifid, 

 rarely 2 ; stigmas obtuse or acute (fig. 655). Fruit succulent or 

 capsular (fig. 656), 1-4-celled, with septifragal and septicidal, or cir- 

 cumscissile dehiscence. Seeds albuminous ; embryo curved or spiral 

 (figs. 659, 502); cotyledons corrugated (fig. 658) or inconspicuous ; 

 radicle inferior. Herbs or shrubs, usually twining, sometimes para- 

 sitical, often with a milky juice, and with alternate, undivided or lobed, 

 exstipulate leaves, rarely leafless. They occur chiefly in tropical and 

 temperate regions. The order has been divided into two suborders: 

 1. Convolvulese, true Bindweeds, leafy plants, with the corolline tube 

 not scaly, embryo curved, cotyledons conspicuous. 2. Cuscuteaa, 

 Dodders, leafless parasites, having scales on the corolline tube, embryo 

 spiral and filiform (fig. 502), cotyledons inconspicuous. There are 45 

 genera, and upwards of 700 species. Examples Convolvulus, Ipo- 

 moea, Exogonium, Dichondra, Cuscuta. 



