122 Transactions. — Zoology. 



" In Bourn's P. stuarti the atria appear to be like those of 

 Acanthodrilus. — F. E. B." 



Genus Acanthodrilus. 



Acanthodrilus annectens, Beddard. Quart. Jour. Mic. Sci., 

 vol. xxix. 



In rich unbroken land, and in moist earth near water- 

 courses and swamps, this species is generally common. It is 

 readily distinguished from all other Acanthodrili by its 

 variegated colours of white and pink. In habits it is sluggish, 

 and secretes a whitish fluid when handled or otherwise re- 

 moved from the burrows. The species vary much in size, the 

 larger forms occurring in rich black mould on the moist edges 

 of swamps. Its specific structural characters are thus defined 

 by Beddard : — 



" This species combines to a certain degree the characters 

 of two other New Zealand Acanthodrili recently described by 

 me — viz., A. multiporus and A. novce-zealandia ; not, however, 

 to so marked an extent as might lead one to infer the possi- 

 bility of its being a hybrid. It is a comparatively small worm, 

 measuring about 3in. in length. :;: 



"External Characters. — The setae are paired, the individual 

 setae being at some little distance from each other. The 

 clitellum occupies segments xiii.-xx. (inclusive) ; the glandular 

 modification of the epidermis is not developed on the ventral 

 surface, as is usual in this genus. The anterior end of the 

 body is somewhat swollen, and the segments here are some- 

 what difficult to map owing to the division of the segments 

 into numerous annuli. In these particulars the present 

 species agrees very closely with A. multiporus. The atrial 

 pores are upon the seventeenth and nineteenth segments, and 

 correspond in position to the outermost of the ventral pair of 

 set33. They are placed upon the summits of prominent 

 papillae ; the two pores of each side are connected by a groove. 

 In one specimen the pore of the vasa defer entia was visible 

 upon the eighteenth segment. As a rule these pores are invi- 

 sible. The oviducal pores are paired, and lie upon the four- 

 teenth segment ; each is placed in front of, and a little to the 

 inside of, the ventralmost seta of the ventral pair. The 

 spcrmathccal pores are in the furrows separating segments 

 vii.-viii. and viii.-ix. ; they correspond in position to the atrial 

 pores. The nephridiopores are visible in most of the segments 

 of the body ; they lie in front of the outermost seta of the 

 outer pair. 



" Internal Anatomy. — The most remarkable fact about the 



* I have lately collected well-developed specimens, with a yellowish 

 clitellum, measuring 4in. and <Uin. in length. — W. W. S. 



