Origin and Development of the Composite. 13 
the ridge which extends around the Pacific and Indian Oceans 
from Fuegia to South Africa. 
In South America 70% of the species of Senecio occur in the 
Andes; the percentage is somewhat lower in North America, but 
some idea can be gained of the development of Senecio in the 
Cordilleran system from the descriptions by Harshberger (34). 
Senecio and Gutierrezia (op. cit., p. 224) are the dominant genera 
of the mesas in the autumn. Senecio again forms a considerable 
part of the rich vegetation of the hanging meadows on the hill¬ 
sides (op. cit., p. 260) and is mentioned among the important genera 
of most Cordilleran regions. Weberbauer (72, p. Ill and p. 113) 
also gives Senecio first place among the genera with many Andine 
species. Greenman (100), who gives a general account of the 22 
sections of North aad Central American species of Senecio , also 
notes that the greatest development of the genus in both North 
and South America occurs on the mountains. The abundance of 
Composites in these and similar regions frequently impresses non- 
botanical writers, e.g., Petrocokino (57) mentions “ fields golden 
with a kind of yellow marguerite ” in the Andes of Bolivia. 
A noteworthy point is that Honduras is a complete bla nk 
and Harshberger (op. cit., p. 663) mentions no Senecio in the 
Guatemalan region, which includes Honduras, nor is there any 
endemic species recorded from Nicaragua or San Salvador (cp, 
Hemsley, 107). 
In the arctic and subarctic regions there is naturally no 
abundance of local species. The next region of concentration is 
in China, especially the south-eastern region, which is closely 
connected with the eastern part of the Himalayan concentration. 
The western part of the Himalayan concentration connects with 
a smaller development of local species along the Hindu Kush and 
Elburz Mts. This in its turn leads on to a stronger development 
along the Caucasus and through Asia Minor to the Balkans, 
Carpathians, Alps and Pyrenees. 
Still following the path of migration along the mountains 
there is some slight development of local species in Arabia, con¬ 
necting with a larger development in Abyssinia. The region of 
concentration extends in some degree along the mountains of east 
tropical Africa, culminating in the 54 endemic species of Senecio 
in Madagascar and the 280 local species which have been recorded 
for South Africa. 
