466 MR. G. BENTHAM ON COMPOSITAE. 
Inuloidese, in Helianthoidee, and in Cynaroides; and our two 
genera are in other respects totally at variance with Vernoniacez. 
They appear to me to have the style and several other characters of 
Arctotidez, and really almost to close up the gap between the 
S.-African Arctotidee (Gorteriex) and the northern Cynaroidez 
(Echinopsidez); and one genus has the geographical position of the 
former, the other of the latter, both included in the general range of 
the two tribes. 
ll. Cynaroidee. 
The Cynaroide form the largest tribe in the northern hemi- 
sphere of the Old World, where they do not, with the exception of 
one very widely spread eastern species, cross the tropics south ward, 
their only extension, and that a sparing one, being into N. America 
and thence down the western ranges of mountains to Chili, with 
one Australian species. They comprise near 900 species in about 
36 genera ; the subtribes into which they are divided are not well 
marked out, or, in some respects, perhaps too artificial, although 
there are some very distinct genera. Asa whole, taking geographi- 
cal distribution into account as a check upon structural characters, 
the tribe is definite in itslimits; their habit, involuere, receptacle, 
corolla, anthers, and styles are all characteristie, and though each 
one may show exceptions, these exceptions never occur in all the 
organs at once. Their nearest connexions are with the Muti- 
siacese on the one hand, and the Arctotidee (Gorteriee) on the 
other ; but the nearest connecting genera belong to these tribes 
respectively, and not to Cynaroidew. Not following precisely the 
subtribes of the * Genera Plantarum,’ we will consider successively 
Six prominent genera—Centaurea, Saussurea, Cnicus, Carlina, 
Xeranthemum, and Echinops, taking under each the smaller genera 
more or less diverging from them—the first three of which are the 
only ones of the tribe which extend into America. The great 
centre of the whole tribe is the Mediterranean region, taking it in 
its extended area so as to include Persia; and many genera are 
limited to its eastern portion. 
Centaurea, as most generally understood, is a genus of about 320 
species, having the geographical range of the tribe, most abundant 
in the Mediterranean region and the Levant, but extending in 
America and Africa to the utmost limits of the general area of 
Cynaroidem. Although very fairly defined as a whole, it presents 
such infinite variety in the tips or appendages of its involucral 
