278 Transactions. — Zoology. 



Plagiochseta sylvestris, Hutton, 1876 (= P. punctata? 



Benham, 1892). 



In the year 1876 Captain Hutton* gave a brief account of 

 the external anatomy of several New Zealand earthworms, 

 amongst which were two species which he placed in the 

 genus Megascolex — viz., M. sylvestris and M. lineatus. In 

 the year 1892 I gave a detailed account! of the anatomy of 

 a worm collected on Maungatua, for which it was necessary 

 to create a new genus, and I termed it Plagiochseta punctata. 

 At that time I was ignorant of Captain Hutton' s article ; but 

 in 1892 Mr. BeddardJ suggested that in all probability 

 M. sylvestris belonged to this new genus. This supposition 

 was confirmed by me when, in 1898, I had the opportunity 

 of examining Hutton's types, § preserved in the Otago Uni- 

 versity Museum, and in a note upon these types I pointed 

 out that " it is difficult at present to determine whether 

 M. sylvestris is or is not identical with P. punctata" ; and I 

 recognised that M. lineatus belonged to the same genus. A 

 renewed examination of the type, and of other specimens col- 

 lected in the neighbourhood of Dunedin, where the type was 

 collected, has enabled me to establish this identity, and,, 

 further, to indicate the differences, external and internal, 

 that exist between P. sylvestris and P. lineatus in a more 

 detailed manner than was possible in my former note. 



Habits. — P. sylvestris occurs in rotten logs in the remains 

 of the bush country that forms the Town Belt around Dun- 

 edin, as well as on the slopes of Maungatua, and no doubt 

 elsewhere. It is still pretty plentiful in our Town Belt, and 

 I have found it especially in fallen Griselinia trees. The 

 colour is chocolate, and closely resembles the vegetable 

 mould — the digested w r ood — amongst which it lives. It is 

 marked, as I noted in 1892, with white spots, in which the 

 chaetae are inserted, while the nephridiopores are also indi- 

 cated by still more conspicuous white spots, readily visible to 

 the naked eye. The species is extremely active, and moves 

 in a straight line with great rapidity, using its mouth as an 

 organ of adhesion. It contracts its bodv to about half its 

 length, then thrusts its head forward and extends itself 

 fully ; there is no wriggling or undulation of the body. 

 When extended one specimen measured was 2 in. (50 mm.) ; 



* Hutton : "On New Zealand Earthworms in the Otago Museum " 

 (Trans. N.Z. Inst., ix., p. 352). 



f Benham : "Notes on Two Acanthodriloid Earthworms from New 

 Zealand " (Quart. Journ Micros. Sci., xxxiii., p. 294). 



| Beddard : " On some New Species of Earthworms from various 

 Parts of the World " (Proc. Zool. Soc, 1892, p. 667). 



§ Benham : "A Re-examination of Hutton's Types" (Trans. N.Z,. 

 Inst., xxxi., p. 156 ; and Ann. Mag. Nat. Hist. (7), iii., p. 137). 



