568 



THE CONVOLVULUS FAMILY. 



1. Blue Polemonium. Polemonium cseruleum, Linn. 



(Fig. G78.) 



(Eng. Bot. t. 14. 



Fig. 678. 



Greek Valerian or Jacob's Ladder-) 



Stock perennial, the radical leaves 

 forming dense tufts, their common stalk 

 6 inches long or more, bearing from 11 

 to 21 lanceolate, entire segments or leaf- 

 lets of a tender green. Stems erect, 

 1\ to 2 feet high, bearing a few smaller 

 pinnate leaves, and a rather showy ter- 

 minal corymb or panicle of flowers. 



Widely diffused over the higher north- 

 ern latitudes of Europe, Asia, and Ame- 

 rica, extending also into the mountain- 

 regions of central Europe and Asia. In 

 Britain it is found in several parts of 

 the north of England, but has been so 

 long cultivated in cottage-gardens, and 

 seeds so readily, that it cannot be pro- 

 nounced with any certainty to be truly 

 indigenous. Fl. summer. 



L. CONVOLVULUS FAMILY. CONVOLVULACE^. 



Herbs, usually twining or prostrate (rarely, in some exotic 

 species, erect or shrubby), with alternate leaves, or leafless and 

 parasitical ; the flowers, often very showy, growing singly or 

 several together on axillary peduncles. Calyx of 4 or 5 distinct 

 sepals, often very unequal. Corolla usually campanulate (but 

 varying in form in exotic species), plaited in the bud, with 4 or 5 

 lobes, or nearly entire. Stamens 4 or 5, attached near the base 

 of the corolla. Ovary and capsule containing 2, 4, or 6 seeds, and 

 often divided into 2, 3, or 4 cells, the partitions very thin, and 

 remaining attached to the central column, and not to the valves, 

 when the capsule bursts. Styles simple, with 2 or rarely 8 stig- 

 niatic lobes, or 2 distinct styles. 



An Order rather numerous in species, and widely spread over the 

 warmer and temperate parts of the globe. The exotic genera, Jpomcea, 



