DISTRIBUTION OF TRIBES. 423 
have afew African representatives ; for many groups of the former 
‘ave been found in South Africa, and a few species referable to the 
latterin Madagascar. The genus extends also into North Africa, 
Europe, and Central Asia—that is, into the Mediterranean region 
taken in avery extended sense. All these northern species belong 
to the section Stechas, also represented in South Africa, with two 
monotypic exceptions: one is Cladocheta, which, however, might 
well be included in Stechas, although De Candolle generically re- 
moved it on account of the sete of the pappus being more or 
less united in bundles; but the little value of this character is 
shown by its occurrence likewise in other species, as, for instance, 
. in the Australian monotypic section Acanthocladium, which has 
the habit of the tropical-African H. spinosum and H. horridum, 
neither of which has the same pappus. The other exception in- 
cludes H. frigidum, Willd., and H. virgineum, DC., dwarf alpine 
species, only known, the one from the mountains of Corsica, and 
perhaps of Lebanon, the other from Mount Athos in Greece, both 
very unlike any other species growing north of the equator. The 
radiating involueres are those of the southern Xerochlene; and the 
whole plant has much outward resemblance to the New-Zealand 
H. (Gnaphalium, Hook. f.) prostratum and bellidioides, but with 
the densely silky-villous achenes of several Heliptera. 
Helipterum cannot well be called a good natural genus, but 
rather a collection of local South-African or Australian subgenera 
or sections, retained as a distinct group rather for convenience’ sake, 
and solely founded on the artificial character of a plumose pappus; 
andeven tbat fails to draw a distinct line separating it from some 
species of Helichrysum. Ytis much more Australian than African; 
for of 42 species, 30 belong to the former region, and 12 to South 
Africa;it is in Australia also that it blends most with Helichrysum ; 
in South Africa the two genera are more distinct. We have, in 
the ‘Genera Plantarum,’ characterized four sections, of which one 
small one, Syncarpha, with two species, is South African, two, 
Pteropogon ten species and Monencyanthes seven species, are 
Australian; the principal one, Euhelipterum, is common to both 
regions, although even here there is a slight difference; the 
majority of the Australian Euheliptera have radiating involueres, 
which are exhibited only by very few of the South- African species. 
Stenocline is a small genus of a more tropical character than any 
others of the Helichrysez, and the only one common to the New and 
the Old World. 1t has eight species, of which six are Mascarene 
