564 



CL. POLEMONIACE.E. 



PolemoHium. Flower cut vertically (mag.) 



Polemonium. 



Stamen, inner face 



(mag.). 



Polemonium catruleum. 



Polemonium. Diagram, 



Polemonium. Fruit (mag.). 



Polemonium. 



Seed, entire and cut 



vertically (mag.). 



Polemontaceee are closely allied to Convolvulacea (which see). They approach Hydrophylkce in the 

 alternate leaves, hypogynous and isostemonous corolla, loculioidal capsule, axile embryo and copious albu- 

 men ; but in ITydrophyllece the ajstivation of the corolla is imbricate, the ovary sub-2-celled with parietal 

 placentation, the radicle superior, and the albumen cartilaginous. Hydroleaceee agree and differ similarly ; 

 besides which the styles are distinct and the ovules horizontal. Polemonwcece are also distantly allied to 

 Gentianece (which see). 



Polemoniacece mostly inhabit the west of extra-tropical America ; very few occur in the temperate 

 and cold regions of the Old World. The Jacob's Ladder, or Greek Valerian (I'olemonium cceruleuin), 

 is mucilaginous, nauseous in scent and bitter ; in some countries its leaves are applied to ulcers following 

 contagious diseases, and the Russians giv a decoction of it in cases of hydrophobia. 



