322 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



be distinguished, crossed by still finer concentric grow th -lines ; in 

 most examples this sculpture is, however, lost, the shells being more or 

 less eroded. The colour of the type is light brown, with a few dark 

 concentric bands and spots around the margin ; the common conoidal 

 form is dirty white, with radiate brown or black lines which reach up 

 to the apex, or, more commonly extend only over the lower half of the 

 shell, the upper half being tessellated with black and white. Apex at 

 about the anterior third, directed forward and sliarply pointed, but 

 very often rounded off by erosion; the slopes are broadly convex 

 posteriorly, straight or distinctly concave anteriorly. Interior light 

 brown to white ; spatula dark brown, with patches of a lighter colour, 

 sometimes quite white ; margin sharp, with brown dots and lines. 

 Length 4'5, breadth 4, height 3-5 mm. Type. 



,, 9, ,, 7, ,, 4 ,, The common form. 



Dentition: Hutton, Trans. N. Zeal. Inst., vol. xv, p. 127, pi. xv, 

 fig. K. The Figs. 24-25 are a copy. The cutting-points are shorter 

 than usual in this group, but they were longer in several examples 

 I examined. 



Hah. — The type is from Sumner, near Christchurch, where it may 

 be found living on rocks between clusters of Modiolus atcr. In my 

 collection the species is represented from the following localities: 

 South Island : Sumner, Heathcote Estuary, Lyttelton, Oamaru, 

 Grej'mouth. Taumaki Island, 10 fathoms. North Island: Cook 

 Strait, Evans Bay, Port Nicholson, East Cape lighthouse, Auckland 

 Harbour, west coast between Manukan and Kaipara. Also Chatham 

 Islands. 



The specimens selected as the type by the late Captain Hutton 

 represent really an extreme form of the species, the high conical and 

 rounded form being no doubt due to environment ; it has a striking 

 likeness with the figures given by Quoy & Gaimard, but when 

 specimens are compared there is no more doubt that the New Zealand 

 form is quite distinct from the much larger, more solid, and somewhat 

 differently coloured Australian species. 



I have specimens from Tasmania which correspond exactly with 

 A. parviconoidea. The variability of this species in shape and colouring 

 is considerable. Type in the Canterbury Museum, Christchurch. 



AcM^A PAKvicoNoiDEA, Sutci, var. LEUCOMA, n.var. 



Shell small, thin, opaque, ovate, depressed, conoidal ; sculpture, if 

 any, lost by erosion ; colour white, apex obtuse, at about the anterior 

 fourth to fifth. Inside white, spatula greenish-white, margin sharp, 

 with a few small brown dots. Length 7, breadth 5'5, height 2"5 mm. 



Dentition unknown. Type in my collection. 



Hob. — Heathcote Estuary, near Christchurch (H. S.). 



ACM^A PARVICONOIDEA, Sutcr, Var. NIGROSTELLA, u.vtir. PI. XXVII, 



Figs. 26-29. 

 The young shell (Fig. 26) reveals under a good lens distant, low, 

 radiate riblets and fine concentric growth-lines. The colour is white, 

 the centre being occupied by a purplish-black, four to nine rayed star ; 



