iQo8.] W. MiCHAEivSEN : Oligochœta of the Indian Empire and Ceylon. 127 



south-east this island was widely separated from the Burmese Province. The im- 

 migration of Pheretima from Burma into the Himalayan-Bengal Province can be only 

 of very recent date. It has not yet brought about the result of important settlements 

 in Bengal of the genus Pheretima, which is so distinctly prevalent in Burma. The 

 scarce occurrences of perhaps endemic Pheretima in Bengal 'and the Peninsula of 

 India) are not even quite certain. Another great island occupied the southern part 

 of India including Ceylon, the recent dominion of Drawida ,N otoscolex , Megascolex and 

 Lampito. These genera seem to be restricted totally to the region of this "South Indian 

 Island." Only some feeble outposts, not even certainly endemic, of Drawida have 

 been sent northwards. The separation of Ceylon from this South Indian Island 

 must be of a very recent date. We may clearly see even now on the map the 

 former connection between Ceylon and the main part of the formerly greater South 



Dominion cf 



Drawida | ^__^_ Pheretima >SA^5^\îS^^ 



Moniligaster j — Octociiaetus I -//////// 



Notoscolex I .:-_vji-.---.-.-.-- Hoplooliaetella I ///////'' 



IVIegascolex j :-----;------■-•-: Eutyphoeus |llll||ll|||||lll 



Perionychella :i;l;l;i!ii;l|ii|; Eudicliogaster -,"V,\\_\^\ 



Indian Island. Adam's Bridge is a relic of this former connection. The geographi- 

 cal connection between Ceylon and South India represents in a manner such an 

 occurrence of change in the configuration of land and sea, viz., the dividing of a 

 formerly larger land or island into two parts. There must on the other hand have 

 been a connection between the North Indian Island and the South Indian Island at 

 a far distant period, for the genera Odochœtus and Perionyx occupy both districts 

 and there are other terrestrial Oligochsetes which can only have immigrated from 

 the North Island into the South Island, viz., the genus Lampito, doubtless derived 

 from Perionychella. A third great island may have occupied the western part of 

 India, the dominion of the genus Eudichogaster , with questionable connections with 

 tropical Africa. Eudichogaster is the only genus that has been found here endemic. 

 But this part of India is not yet explored fully enough. We do better to defer the dis- 

 cussion about this part. 



