ORDER JEQ.VA1AS. 165 



Massachusetts to the Gulf of Mexico, the number of 

 species slowly increasing to the south and west, to 

 the number, now, of about 6. The leaves in all are 

 long, and mostly lanceolate, with their margins ser- 

 rated, and the flowers, resembling those of minute 

 purple thistles, form a considerable compounded co- 

 rymb. The species are best distinguished by the 

 calyx, which varying in size, is either ovate, or more 

 rarely, hemispherical, formed of imbricated scales, 

 either merely acute and closely laid over each other, 

 or else ending, as in V . noveboracensis, in filiform 

 points. These points are carried to an unusual length 

 in a yet undescribed species of Arkansa territory, in 

 which the flowers are large and hemispherical, and 

 the calyx so appendaged and squarrose as to form, 

 almost, a Medusa's head ; in this, the leaves are like- 

 wise very long, and narrow. Besides the generic 

 character derived from the calyx (which is that of 

 SerratuJa), the stigma, as in the following genus, is 

 bifid ; but the most decided trait of Vernonia is in 

 the existence of a double pappus, the exterior short 

 and chaffy in some degree, and the interior capil- 

 lary. 



JLiatris, allied to Vernonia, is one of the most ele- 

 gant genera of the class, peculiar to the United 

 States, and of which there are known 12 or 13 spe- 

 cies. The genus is very naturally divisible into 2 

 sections ; namely, those with round tuberous roots, 

 and undivided or simple stems ; and those with fibrous 

 roots, and flowers in corymbs. Those of the first 

 section, whose species extend the farthest north, are 

 remarkable for the grass-like narrowness of their 

 leaves, elegantly contrasted with the showy magnitude, 

 and beautiful pink purple of their autumnal flowers. 

 To this section belong those which have been esteem- 

 ed for the bites of poisonous reptiles ; and hence 



