172 Transactions. — Zoology. 



terior half of the body is frequently off the ground, and 

 placed down until the posterior half is drawn forward. These 

 alternate movements, or modes of progression, are repeated in 

 rapid succession. It is a very sensitive species, and if touched 

 a little roughly will twist itself violently about, often leaj^ing 

 several inches along or off the ground. These remarks may 

 enable collectors to identify the species when met with. 

 Herewith I give an abstract of Beddard's description of the 

 species : — 



" The general appearance of the worm is very different from 

 that of the other New Zealand Acantlioclrilidce. which I have 

 so far had the opportunity of studying — so different that it 

 was unnecessary to dissect the species in order to ascertain its 

 distinctness. All the New Zealand AcanthodrilidcR with the 

 exception of the present species are either devoid of pigment 

 in the skin, or, if pigment is present, the worms are of a 

 brownish colour. Acantliodrilus smitlii is (after preservation 

 in alcohol) of a violet colour, the clitellum being whitish- 

 yellow ; the ventral surface of the body is the same colour as 

 the clitellum. 



" The worms are slender, measuring up to 75mm. in 

 length, with a diameter of 3mm. at the widest part of the 

 body. An individual of this size consisted of 114 segments. 



" The prostomium completely divides the buccal segment, 

 as it does in the New Zealand species, Acanthodrihis novce- 

 zcalandm, &c. 



"The setge are paired, and the pairs are equidistant, the 

 body being thus divided into four equal areas. There is no 

 difference in size between the setse of different segments. 



"The clitellum occupies segments xiii.-xix.; it is saddle- 

 shaped, and is not developed ventrally beyond the outermost 

 of the two ventral setae. 



" I could find no dorsal pores. 



"The nephridiopores are very evident ; they alternate in 

 position from segment to segment, as is the case also with 

 other species of Acanthodrihis from New Zealand. They 

 sometimes lie in front of the dorsal, sometimes in front of the 

 ventral setae. When they open in front of the ventral they 

 aj)pear to be particularly related to the outer of the two setae. 

 When, on the other hand, they appear in front of the dorsal 

 setae the orifice is in front of the innermost of the two setae 

 which constitute the pair. 



" The spermatothecal pores lie on the border-line, between 

 segments vii./viii. and vhi./ix. They lie in front of and to 

 the outside of the ventral pair of setae. 



" The atrial pores are upon segments xvii. and xix. ; their 

 position corresponds exactly with that of the ventral pair of 

 setae, which are absent from these segments. The ventral are, 



