22 Annals of the South African Museum. 



V v 



EEMAEKS ON THE DISTRIBUTION OF ARENICOLA 



ASSIMILIS. 



Arcnicola assimilis, in the wide sense, that is, including the 

 variety affinis, is evidently the characteristic species of the southern 

 regions. Typical examples have been recorded from Punta Arenas 

 (Strait of Magellan), Uschuaia (Beagle Channel), and South Georgia. 

 Examples referable to the variety affinis are known from Uschuaia 

 (a gill-less post-larval specimen), Lapataia Nueva (Beagle Channel), 

 Susanna Cove (Strait of Magellan), the Falkland Islands, Kerguelen, 

 Macquarie Island, Campbell Island, Stewart Island, and Otago 

 Harbour (New Zealand). The most northerly station from which 

 this species has hitherto been recorded is the last named, which is 

 in about 46 S. latitude. I have recently received, from Professor 

 H. B. Kirk, two specimens from Plimmerton, near Wellington, about 

 41 S., which shows that A. assimilis var. affinis extends into the 

 North Island of New Zealand. Professor W. A. Haswell has sent 

 me a few specimens from Burnie, on the north coast of Tasmania 

 (also about 41 S.) which belong to the same species and variety. 

 This is the first record of Arcnicola assimilis from the Australian 

 sub-region. The examples from Liideritzbucht and Table Bay not 

 only extend the records to the coast of Africa but to a latitude 

 considerably further north than any previous record, Table Bay 

 being in latitude 34 S., and Liideritzbucht in 26 40' S. (ap- 

 proximately) . 



In a recent publication" I directed attention to the distribution of 

 A. assimilis as supporting the view that there was formerly a more 

 extensive Antarctic continent. The distribution of this species of 

 Arcnicola presents, in fact, a remarkable parallel to that of certain 

 Oligochaetes. Mr. Beddard I pointed out that the characteristic 

 earthworms of New Zealand are Acanthodrilidse, that the same 

 family is equally characteristic of Patagonia, and that the only 

 earthworms known from the intervening localities the Falklands, 

 South Georgia, Marion and Kerguelen Islands also belong to this 

 family. Mr. Beddard regarded these facts as evidence in favour of 

 a former greater extension northwards of the circurn -polar Antarctic 



* " The Annelids of the Family Arenicolidfe of North and South America ..." 

 in Proc. U.S. Nat. Mus., vol. 39, pp. 1-32. Washington, 1910. 



f- Beddard, F. E., " A Monograph of the Order of Oligochseta," Oxford, 1895, 

 p. 154. See also, by the same author, "A Text-Book of Zoogeography," Cam- 

 bridge, pp. 60 and 170. 



