linearia, obtusa, compressa, glabra, recurvata. Achenia in radio tantúm 
maturescentia, cuneiformia, compresso-pentagona, glabra, nigricantia, foliolis 
involucri obvoluta exterioribus, umbilico emarginaturá unilaterali! apice 
calva : disco epigyno minimo.—Don MSS. 
** The present shewy species is distinguished from the 
rest of its congeners by its elevated hairy receptacle, which 
in the others is depressed and naked. "The genus, founded 
by Molina on a Chile plant, famous for the oil expressed 
from its seeds, although consisting of but few species, has 
a pretty extensive geographical range, being found in the 
temperate regions in both hemispheres of the American 
continent. It is nearly allied to Unwia and Siegesbeckia ; 
but the former is essentially distinguished by its simple 
involuerum, and the latter by its paleaceous receptacle. 
The florets of the ray in Siegesbeckia are also most fre- 
quently bilabiate, and those of the disk quadrifid, and 
sometimes tetrandrous. This genus exhibits a striking 
example of a fact, which I have elsewhere (Edinb. New 
Phil. Journ. Oct. 1831) shewn, namely, that the presence 
of papille on stigmata affords no evidence of their fertility ; 
for here the florets of the disk with almost smooth stig- 
mata uniformly perfect seeds; while in Madia, where the 
sugmata are thickly beset with bristly papillee, the florets 
of the disk are generally sterile. This group, for which I 
have preferred the name of Melampodee, as being derived 
from a genus affording a better type of it than either Milleria 
or Siegesbeckia, is characterised by a herbaceous involucrum, 
composed of an almost definite number of nearly equal 
leaves, by the florets of the disk rarely perfecting seeds, 
and by the turbinate achenia being destitute of pappus or 
seed-crown, and furnished at the top by a very small 
epigynous disk. It will contain, besides Melampodium 
and the present genus, Centrospermum (hardly distinct from 
the first), Jegeria, Unzia (from which Villanova of Lagasca 
is scarcely to be separated), Eriocoma, Polymnia, Montanoa, 
Zaluzania, Siegesbeckia, Milleria, and Sclerocarpus, compre- 
hending, in fact, the greater part of M. Cassini's Hélianthées- 
Millériées. This learned Botanist. has referred Melam- 
podium to his first group, or Millériées-vrais-réguliéres, and 
Milleria and Unvia to his second group, denominated 
Millerites-vrais-irregulieres ; while Madia, Villanova, and 
