Benham. — The Sipunculids of New Zealand. 177 



Some of the individuals are males, others are females, but 

 I could detect no difference in size or colour between the 

 sexes. 



Dendrostoma, Grube (em. Keferstein). 



D. aeneum, Baird (= Sipunc^dus ceneus, Baird, 1868 = Si- 



punculus hitulentus, Hutton, 1879 = Phascolosoma Imttoni, 



Benham, 1903). (Index F.N.Z.) 



In the tube (b) above mentioned is a single sipunculid, 

 which, except in its smaller size, closely agrees with Hutton's 

 diagnosis of Sijyimculus lutulentus ; and, moreover, was col- 

 lected at Cape Campbell, the locality ascribed to that species. 

 To this matter I will return after describing the worm ; for, 

 in addition to this individual, I have received a considerable 

 number of specimens from Auckland and the neighbouring 

 coast. Several of these, as well as the above individual, have 

 been opened. 



Form. — [a.) The cylindrical body is broader posteriorly 

 than anteriorly, but the hinder extremity is bluntly rounded. 

 There is no definite " pyriform swelling," such as Captain 

 Hutton describes for his S. lutulenUis, in any of my specimens, 

 and in the above-mentioned individual (b) the hinder end is 

 retracted, so that it is even more rounded, more obtuse, than 

 usual ; and a similar condition is presented by some others in 

 which the introvert is retracted. 



{b.) The introvert is quite short, barrel-shaped, so that its 

 middle is of greater diameter than the anterior extremity of 

 the body. The mouth is surrounded by a four-lobed ten- 

 tacular crown, the base of which is surrounded by a collar, 

 rendered conspicuous by its deeper purple margin. Each 

 lobe of the tentacular crown is usually dichotomously divided 

 twice successively, so that there are in all 16 short lobules. 

 (There is some variation in actual details, for sometimes only 

 one dichotomy exists ; in other cases each lobe ends in 5 or 6 

 lobules.) Each lobule is fringed on each side by a single row 

 of finger-shaped tentacles or cirri, of which the proximal ones 

 are much larger than the distal ones, there being a gradual 

 diminution in size. There are usually 5 tentacles on each 

 side of a lobule, together with a terminal small one, though 

 I note that often there are only 4 on the inner margin of 



hinder end of the body, of a white cap-shaped mass of calcareous 

 material, which, associated with a circular white patch at the base of 

 the introvert, led me, on inspection, to refer it to the genus Aspidosiphon, 

 and as such I included it, most unfortunately, in the Index Faunae 

 N.Z. On closer examination, however, it turned out that the circular 

 patch is situated on the ventral side instead of on the dorsal side, and it 

 is readily scraped away, consisting apparently of some sort of secretion ; 

 while the posterior cap consists of a mass of tri-radiant calcareous sponge- 

 spicules, closely aggregated together, and adhering quite firmly to the 

 body- wall. 



12— Trans. 



