132 Transactions. — Zoology. 



Affinities. — There is undoubtedly a very close affinity with 

 the species A. annectens and A. paludosus, which, as Beddard 

 has shown, differ in many respects from other members of 

 Acanthodrilus, and approach in some respects to Octochcetus. 

 The present species is larger than either of these. In colora- 

 tion and in certain details — in absence of muscular duct to- 

 the nephridium, absence of penial chaetae — it resembles 

 A. annectens, from which it differs, however, in the position 

 of the gonads, in the form of the spermatheca, and some other 

 details: while from A. paludosus its size marks it off, as- 

 well as such details as the position of sperm-sacs and the 

 form of spermatheca. 



In a previous note (see page 123) I have referred to the 

 fact that Michaelsen (loc. cit., page 233) has proposed a sub- 

 division of the genus Acanthodrilus into a number of genera. 

 "With some of his reasons I agree, but I do not as yet feel 

 convinced of the possibility of erecting the genera Maoridrilus 

 and Notiodrilus for such species respectively as have nephri- 

 diopores alternately in line with dorsal and ventral chsetse, 

 and for those in which all the pores are in line. As subgenera 

 the names are certainly convenient, and the present species 

 belongs to the subgenus Notiodrilus. 



2. Acanthodrilus macquariensis, Beddard. 



Two specimens were collected by Dr. Colquhoun. The 

 species was originally described by Beddard(7) from two 

 sexually mature and several immature specimens. Its great 

 interest lies in the fact that it has closer affinities with the 

 species occurring in Patagonia, the Island of South Georgia, 

 and the Falkland Islands than with those of New Zealand. 



Colour. — Light greenish-brown (in formol). The pigment, 

 confined to the dorsum of the anterior 30 segments, while- 

 posteriorly the pigment is absent. 



Dimensions. — A small cylindrical worm, measuring about 

 H in. by T 3 g in. (i.e., 40 mm. by 4-6 mm.) in diameter. Tbe 

 body consists of 83 and 85 segments respectively. (Beddard 

 finds 100 segments.) 



The prostomium is prolonged backwards through half the 

 length of the buccal segment. (Beddard states that it does 

 not divide this segment.) 



The chatce are very nearly equidistant, though the dorsal 

 couple (cd) are slightly further apart than the ventral. The 

 relative distances, as measured on the skin spread out on a 

 slide, are : ab = 4, L = 5, cd = 5, V = 7, D = 10. 



The clitellum covers segments 13 to 16 and 13 to 17 in 

 the two individuals ; the intersegmental grooves, however ,_ 

 remain distinct, and the colour is scarcely different from that 



