SOME RECENT MEMOIRS UPON OLIGOCH/ETA. 191 



can Continent, twenty are members of the genus Acantho- 

 drilus, eleven are Microscolex and one is a PericJiesta. Besides 

 these are a few obviously imported Lumbricus and 

 Allolobophora from Europe or North America. I say 

 obviously imported because these worms are only found in 

 cultivated ground and near the coast ; as civilisation is left 

 behind these species decrease and are replaced by the 

 truly indigenous species. Among the twenty species of 

 Acanthodrilus are included two or three which occur in the 

 Falkland Islands and in South Georgia. Turning to New 

 Zealand we find that out of twenty indigenous species nine 

 are Acanthodrilus, six belong to the closely allied genera 

 Octochcehis, Deinodrilus, and Plagiochcsta, three are Micro- 

 scolex, while the two remaining are a Perichceta and a 

 Megascolides, two genera which are eminently characteristic 

 of the adjoining continent of Australia. Between New 

 Zealand and South America is a long stretch of ocean, 

 sparsely scattered over which are islands of volcanic origin. 

 From three of these islands earthworms have been collected. 

 In Kerguelen and Marion Island is a species of Acantho- 

 drilus peculiar to those islands, and I have lately received, 

 and am describing in the forthcoming June number of the 

 Proceedings of the Zoological Society, a second species of 

 that genus from Macquarie Island. The significance of 

 these facts will be more apparent when we consider how 

 far the genera that have been referred to in the fore- 

 going are distributed outside of this antarctic area. Micro- 

 scolex is found in many parts of central and the warmer 

 western regions of North America ; it has been met with 

 also in Europe, Algeria and Teneriffe. Acanthodrilus 

 occurs in Australia where it is represented by three species, 

 all of which however inhabit the eastern half of the island 

 continent, that part in fact which is nearest to New 

 Zealand ; Acanthodrilus has one species in Natal, one in 

 New Caledonia and two in North America. 



We have evidently therefore a fauna of earthworms 

 peculiar to the antarctic region, into which more northern 

 forms have been able to make but slight inroads and from 

 which but few stragglers have wandered. 



