DISTRIBUTION OF TRIBES. 439 
7. The main subtribe of VERBESINEA comprises about 570 spe- 
cies distributed amongst 57 genera, many of them natural enough, 
but distinguished by characters of comparatively small import- 
ance, sometimes passing into each other, and often very technical 
and very difficult to group together except into very artificial 
series. The great majority are American, many of them restricted 
to that continent or to limited areas within it; but some are well 
represented in tropical Africa, or in a less degree in Asia or Aus- 
tralia, and two small genera are exclusively Mascarene. The 
geographical distribution of the two following subtribes (8. Conz- 
OPSIDEZ,17 genera with 150 species; and 9. GALINSOGE®, 7 genera 
with 80 species) is nearly the same, the one comprising also 
4 small exclusively Old- World tropical genera, and the latter 1 
small Sandwich-Island endemic genus. As the differences which 
distinguish them from Verbesines are also of somewhat minor 
importance (chiefly the shape of the achene in the one case, the 
nature of the pappus in the other), and as the real value of the 
generie distinctions is often as yet uncertain in all three subtribes, 
we may consider the whole as one group, taking the principal 
genera rather in the order of their geographical distribution, com- 
mencing with those American ones which are also represented in 
the Old World by distinct species. 
Wedelia, about forty species, Blainvillea, ten species, slightly 
differing in the pappus, and Aspilia, thirty species, with neutral 
ray-florets, may be regarded as one large genus, chiefly Ame- 
rican, of which each of these divisions includes several Old- World 
species, the whole group also scarcely distinct from several other 
purely American genera. Wedelia itself, as now limited, com- 
prises three tolerably well-marked sections: (1) Stemmodon has 
three or four tropical-American species and one in tropical Asia, 
W. calendulacea, a maritime plant very closely allied to the simi- 
larly maritime West-Indian W. gracilis, although not identical; 
(2) Cyathophora, with numerous tropical A merican, has one insular 
(Galapagos) species, W. frutescens, Hook. f., which appears 
quite distinct from Jacquin's plant of that name, one East-Indian 
species, JV. urticifolia, and one in east tropical Africa ; (3) Wol- 
lastonia, with the pappus very much reduced or disappearing 
altogether, appears to be an Old- World deviation, and is limited 
to tropical and subtropical Asia and Australia. Although usually 
regarded as a genus, there is really nothing but this reduced 
pappus to separate it from Cyathophora; one species, indeed, so 
