THE THISTLE FAMILY. 



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introduction is not recorded, but is known to have been 

 cultivated about one hundred years ago, first being treated 

 as a greenhouse plant ; but as it was found to flower in the 

 open air in autumn, it soon became a great favourite. Other 

 fine varieties have been introduced, as also raised in this 

 country, and Chrysanthemum shows now yearly take 

 place. 



The Dahlia may be considered the next in repute. It is 

 a native of Mexico, and is recorded as being introduced in 

 1789 and 1802. It was supposed there were two species, 

 D. superflua and D. frustranea, but they are now considered 

 to be one. The flowers were originally single, one having 

 pistilliferous rays, and the other barren ; the two now are 

 united under the name D. variahilis. The first plants intro- 

 duced do not appear to have been much valued and were 

 early lost ; but it was again introduced from France, and 

 about 1818 began to be specially noticed in this country, the 

 roots being considered eatable like the potato, but it found 

 no favour. About 1820, seedling plants began to produce 

 double flowers, which florists have now brought to the 

 highest state of perfection. One of the most ornamental 

 spring-flowers of the greenhouse is the well-known Cine- 

 raria^ of which there are many beautiful varieties, varying 

 in shades of colour of white, blue, red, &c., the original 

 species being C. cruenta, a native of Tenerifle. 



Thistles consist of about 200 species of prickly, biennial, 

 or perennial plants, belonging chiefly to the genus Carduus, 

 Cnicus, and Onopordon^ of which 14 or 15 are natives of 

 this country, Cnicus arvensis, and C. lanceolatus, being well- 

 known cornfield and meadow pests. Cardials Marianus is 

 known as the Blessed, Milk, and Mary's Thistle, superstition 

 ascribing the white lines or marks on its leaves to a drop of 

 the Virgin Mary's milk having fallen on it. Onopordon 

 Acanthium, native of the south of Europe, has become indi- 

 genous in this country, but rare ; generally found grow- 

 ing in gardens. It sometimes attains the height of from 

 6 to 8 feet, and has numerous hoary branches, each termi- 



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