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smooth and sessile; the upper ones are alternate: the lube of the 

 corolla twice the length of the calyx ; segments of the border 

 roundish, spreading, of a light purple colour: the flowers appear in 

 June, but seldom produce seeds in this climate. It is a native of 

 North America, flowering from June to August. 



The seventh species has the stems almost upright, simple, and 

 then divided into two branches: the leaves opposite on a simple 

 stem, in five oppositions, soflish, rugged; the upper ones alternate: 

 the flowers from the partings of the stem and the axils of the alter- 

 nate leaves, two together on separate pedicels: the calyx five-parted: 

 the corollas pale blue, with a crooked tube: the flowers appear at 

 the end, of May, or beginning of June, but are rarely succeeded by 

 seeds in this climate. It grows naturally in North America. 



Culture. These are generally increased by parting their roots, 

 as they do not often produce seeds in this climate. The best time 

 for performing this is in autumn, when the stalks begin to decay. 

 The roots should not, however, be divided into too small heads, 

 when they are expected to flower well the following summer; nor 

 should they be parted oftener than every other year, as, when they 

 are too often removed and parted, it greatly weakens the roots, so 

 that they send out but few stalks, and those so weak as not to rise 

 their usual height, and the bunches of flowers are much smaller. 



The large root offsets may be planted out at once where they are 

 to remain; but the small ones in nursery-rows, for further increase 

 in size. 



When the roots are parted and removed, it is a good way to lay 

 some old tan, or mulch, upon the surface of the ground about their 

 roots, to prevent the frost from penetrating; for, as they will have 

 put out new roots before winter, the frost, when it is severe, often 

 kills the fibres, whereby the plants suffer greatly, and are sometimes 

 wholly destroyed. 



The first and sixth sorts may be increased pretty expeditiously 

 by their spreading roots, but the others but slowly this way; of 

 course it is a better method to have recourse to cuttings. The best 

 season for planting the cuttings is about the end of April, or the 



