372 MR. G. BENTHAM ON COMPOSITE. 
herbaceous, Asters ; and there are many instances in other tribes 
where a shrubby or herbaceous habit may similarly assist in 
distinguishing natural genera. Beyond this, habit is systemati- 
cally as vaguea character in Composite as in other orders, acqui- 
ring importance only in geographical botany for the distinction of 
those plant-forms of which Grisebach has made so much use in his 
studies of geographical distribution with reference to climatology. 
The general inflorescence in Composite (that is, the successive 
development of the flower-heads) is invariably centrifugal, whilst 
the ultimate inflorescence (the successive development of the florets 
within the head) is as constantly centripetal; and this circum- 
stance is very important in characterizing the compound inflores- 
cence of the subtribes Lychnophores in Vernoniaces, Lagasceæ in 
Helianthoides, Angianthes in Inuloidex, and of several genera of 
Filaginee, Relhaniee, Buphthalmes, Cynaroidex, £c. In these 
cases numerous capitula, closely sessile on a common receptacle, 
are collected into a globular, oblong, or depressed cluster often 
surrounded by a common involucre, the whole assuming the ap- 
pearance of a single flower-head. This is more especially the case 
when each individual head is reduced to a single floret with two, 
three, or very few involucral bracts. Such compound clusters 
have been sometimes confounded with single flower-heads like 
those of Albertinia, where the very deep and fringed alveoli 
of the receptacle resemble the separate involucres of the compound 
cluster. In such cases the difference between the centripetal 
inflorescence of Albertinia and the centrifugal one of Eremanthus 
has been well pointed out by Schultz Bipontinus. I am not 
aware of any other very marked generie character to be derived 
from the inflorescence of Composite. If in a few instances the 
heads are apparently axillary and sessile, it is from the abbrevia- 
tion of the flowering branch. In Liatris the inflorescence is 
spicate or racemose, but always with the terminal head first 
developed. In this case the genera Trilisa and Carphephorus are 
chiefly distinguished by the corymbose inflorescence, accompanied, 
however, by some other characters. 
Among miscellaneous vegetative characters must be included 
indumentum, to which we have not perhaps paid sufficient atten- 
tion. Mr. Archer, in a paper published in the fifth volume of our 
Journal, has shown its value in the classification of the numerous 
species of Olearia. The stellate hairs have also been shown to be 
a good generic character for the separation of Hieracium and 
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