42 ERYTHEA. 
next tribe in general aspect, and lacks even the clavate style- 
branches of this one, these organs being nearly linear and 
even somewhat compressed, rather than terete and claviform. 
Although the type of the genus has pentagonal achenia and a 
coroniform concreted pappus, a newly discovered Californian 
ally of it displays exactly quadrangular achenes surmounted 
by distinct and conspicuous pappus pales, and equally dis- 
tinct bristles alternating with them. This I have published 
as a genus Biolettia; and, with authors who, like Bentham 
and Asa Gray, make much of this kind of character, allowing 
it to overbalance all considerations of agreement in habit, 
Biolettia will be received in generic rank. But, as the type 
is a Trichocoronis in facies, I now prefer to treat it as an 
aberrant member of that genus, and rename it: 
Trichocoronis riparia. Biolettia riparia, Goseaia Pitt. 
ii. 216. 
The great representative genus in this subordinal group of 
plants is Evparorium, the type of which was familiarly 
known to the ancient Greek and Roman botanists as 
Eupatorion and Eupatorium, with whom it enjoyed a repu- 
tation in medicine. From pre-Linnzan authors it received a 
number of binary names, for example, H#. aquaticum, Gesner 
(1541), EL. adulterinum, Fuchs (1542) H. vulgare, Matthiolus 
(1554), and H. cannabinum, ©. Bauhin (1623). The last of 
these, having been adopted by Linnzus, is the one now 
in use. 
Around this historic type there range themselves in close 
congeneric relation, some half-dozen species of Europe and 
Asia, and something like twenty plants of the Atlantic States 
of North America. But of the several hundreds of Mexican 
and South American species f toHupatorium, 
the greater proportion differ from the typical group in habit, 
and in various and conflicting peculiarities of the inflorescence, 
involuere, etc. Then over and above all these, are an almost 
equal number of allied plants, which have by various 
authorities been disposed in a dozen or fifteen genera, nomi- 
nal or real, all of which would fall into Hupatorium 4s 
