288 SUBANTARCTIC ISLANDS OP NEW ZEALAND. [OligochnHa. 



on the other they lie in 8, 9, and 10, with the pores at the anterior margin of the 

 segment in each ease. Each spermatheca has a large subsplierical ampulla, a 

 short thick duct, which receives at about the middle of its length a pair of small 

 ovoid diverticula (Plate XI, fig. 39). 



Localities. — Auckland Islands : (a.) Magnetic station, Camp Cove ; (W. B. B.). 

 (6.) North Arm, Carnley Harbour ; (Captain Dorrien-Smith). (c.) Magnetic station, 

 Musgrave Harbour; (W. B. B.). {d.) Masked Island, Carnley Harbour; among the 

 roots of StiJbocarpa polaris ; (Aston), (e.) Adams Island ; at roots of Pleurophyllum, 

 Fairchild's Garden ; (W. B. B., February ; Aston, November). (/.) 2,000 ft. ; under 

 stones ; (Speight), {g.) Disappointment Island ; fragmentary ; (Kirk). 



Remarks. — Anatomically, this species appears to differ from the rest of the 

 species of Diporochaeta in having a branched lumen to the prostate, and on that 

 account should perhaps be placed in the genus Perionyx, according to Michaelsen's 

 most recent views on the diagnostic characters of the genera of the subfamily Megas- 

 colecinae.* But, considered from a geographical aspect, this seems an impossible 

 view to take. I cannot persuade myself that it can belong to this genus, which is 

 confined to the Oriental region. This species {D. perionychopsis) is, as has been noted 

 above, widely distributed over the Auckland Group. It lives all round Carnley 

 Harbour, at all heights, from sea-level to the topmost altitude ; is to be met with in 

 soil at roots of plants and under stones ; and it is extremely interesting that of the 

 two worms obtained on Disappointment Island one is of this species. These islands 

 have no commercial intercourse with the Orient — they are, in fact, uninhabited, 

 and, except for a brief period, have always been without inhabitants but for un- 

 willing, shipwrecked mariners. In the year 1850 a small settlement of Europeans 

 was established by Governor Enderby on what is now known as Enderby Island ; 

 the settlers came from New South Wales, and broke up in 1852 ; at the same time a 

 number of Maoris lived on the main island at Port Ross. But this species of earth- 

 worm could not have been introduced by these immigrants, for the genus Perionyx 

 is unknown either in Australia, or the Chatham Islands, whence these Maoris 

 came. Nor could it have arrived there at the time when New Zealand was of con- 

 tinental dimensions, when the country was probably in some connection with the 

 Oriental region, otherwise one would expect to find the genus represented to-day 

 in New Zealand. I do not see how one can explain the occurrence of the genus at 

 these southern islands. It seems to me inore easy to imagine that the slight branching 

 of the prostate lumen has arisen within the genus Diporochaeta. Had it not been for 

 the emphasis which Michaelsen places on the point it would not have occurred to me 

 to discuss any other probability. 



The microscopic structure of the prostate of Pheretima (Perichaeta) was described 

 by Beddard, and later Miss Sweetf investigated the lobate prostate of some of the 

 Australian genera, while Michaelsen| has given an account of that of Perionychella 

 dendyi, a species formerly included in the genus Diporochaeta. From these the prostate 

 of the present species differs in that there are three or more canals in the prostate 



* Michaelsen, Die Fauna S.W. Austral., p. 152. 

 t Sweet, Linn. Soc. Journ. (Zool.), xxviii, p. 109, 1900. 



X Michaelsen, " Oligochaeten von Australien," in Abhandl. aua dem Gebiete Naturwiss, Hamburg, 

 xix, p. 12, 1907. 



