Benham. — On a Neiv Species of Earthworm. 275 



Art. XXX. — On an Earthworm from the Auckland Islands 

 — Notiodrilus aucklandicus. 



By W. Blaxland Benham, Professor of Biology, University 



of Otago. 



[Read before the Otago Institute, 14th October, 1903.] 

 Plates XXII.-XXVI. 

 The material which forms the subject of the present note was 

 collected by Captain Hutton during his recent trip to the 

 southern islands. He was good enough to send it to me 

 early in 1901. The collection consisted of six specimens, all 

 belonging to the same species, which is new to science. 



Notiodrilus aucklandicus, n. sp. 



Colour. — The worms are, in the preserved condition, grey- 

 ish in colour, with grey-brown clitellum, and the preclitellar 

 region sienna-brown. The grey tone is due to the trans- 

 parency of the body-wall allowing the contents of the gut to 

 be seen ; nevertheless, pigment dots are present in the body- 

 wall. 



Dimensions. — The largest specimen measures 93 mm., 

 the smallest 78 mm. ; two others are 82 mm. in length The 

 diameter of the first is 2-5 mm. in middle of body, but of the 

 smallest 3 - 5 mm. The worms are, unfortunately, very soft, 

 and imperfectly preserved, so that in handling the dimen- 

 sions vary. One of the medium-sized specimens consists of 

 107 segments. 



The prostomium is imbedded about one-third into the 

 peristomium, and is epilobic. 



The eight chatce are separate : aa = dd, ab — h aa, be = 

 ■cd > ab. 



The clitellum is not quite fully developed in any specimen, 

 but in the most mature it extends from half 13 to half 17 (in 

 two specimens covers only 13 to 16). The anterior region is 

 complete ventrally, but the under-surface of the 16th segment 

 is devoid of glandular tissue. 



Genital Pores, &c. — The porophores on 17 and 19 are in 

 line with chasta b, which, with a, is absent on these seg- 

 ments. Both these chstae are present on the 18th segment. 

 A spermatic groove, convex outwards, passes over this seg- 

 ment in the usual way. Accessory copulatory tubercles exist, 

 though there is some variability in their distribution ; but 

 from an examination of the five individuals which exhibit 

 them their location is as follows : — 



