220 



BOTANY. 



Besides the true milk-weeds (Asdepias), there are several other 

 genera within the United States, but mostly southern in their 

 distribution. Many of them are twining plants and occasionally 



J an. 



FIG. 123. Anisocarpous sympetalse (Campanulinse) . A, vertical section of 

 the bud of American bell-flower, Campanula (Campanulacese) , x 2. J3, an 

 expanded flower, x 1. The stamens have discharged their pollen, and the 

 stigma has opened. C, cross-section of the ovary, x 3. JJ, flower of the 

 Carpathian bell-flower (Campanula Carpaticd), x 1. E, flower of cardinal- 

 flower, Lobelia (Lobeliacese), x 1. F, the same, with the corolla and sepals 

 removed, an. the united anthers, f/i/. the tip of the pistil. G, the tip of the 

 pistil, x 2, showing the circle of hairs surrounding the stigma. H, cross- 

 section of the ovary, x 3. /, tip of a branch of cucumber, Oucttrbita 

 (Cvcurbitacese), with an expanded female flower (9). J, andrcecium of a 

 male flower, showing the peculiar convoluted anthers (an.), x 2. K, cross- 

 section of the ovary, x 2. 



cultivated for their showy flowers. Of the cultivated forms, 

 the wax-plant (Hoy a), and Physianthus are the commonest. 



The fourth order (Campanulince) also embraces five families, 

 but of these only three are represented among our wild plants. 

 The bell-flowers (Campanula) (Fig. 123, A, D) are examples 



