320 Stapf. — On the Sonerileae of Asia. 
there are no close relations between these groups and § 
Sonerilopsis. 
Not a single species of the subgenus Sonerilopsis , or of the 
genera Brittenia, Phyllagathis, Gymnagathis , S ar copy r amis, and 
Fordiophyton , is found in the Western Peninsula or in Ceylon. 
S ar copy r amis and Fordiophyton almost meet in South-West 
China, and we may look there for their centre of evolution, whilst 
Gymnagathis and Phyllagathis meet in South-East China, 
and Phyllagathis , Brittenia and § Sonerilopsis in the Malayan 
Archipelago. Probably they sprang from the old continent 
in which China and Malaya joined each other, a connection 
which is indicated likewise by numerous zoo- and phyto- 
geographical and even geological facts. In an analogous 
way we may assume a centre of evolution for the § Genuinae 
either in Ceylon and the Southern Ghats, or in a hypothetical 
connection of land which probably has existed between this 
part of India and Malaya. But this centre is evidently much 
younger and must probably also be traced back in the last 
instance to this Sino-malayan continent. 
It is not my intention to take into consideration the re- 
lations which exist between the Asian and the African 
Sonerileae. But I must point to the very significant fact 
that the only connection which exists between them lies 
through Madagascar, and that the Asian Sonerilas are linked 
to the African ones by way of their oldest and least reduced 
type — the pentamerous Brittenia , — which is linked closely to 
the likewise pentamerous Gravesia of Madagascar. 
Thus the Asiatic Sonerilas may be finally regarded as true 
Sino-malayan types, and as a typical instance with which the 
distribution of numerous larger or smaller groups of plants of 
similar origin may be paralleled. 
