316 PEOCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



A. lacunosa, Reeve, is unknown, and it is not identical with ruhicjinosa, 

 ctngulafa, or corticata of Hutton, as Mr. E. A. Smith, of the British 

 Museum, kindly informed mo after sending him the above-named 

 species for comparison. 

 Fossil in the Pliocene. 



2. AcMiEA ciNGULATA, Huttou. PL XXVII, Figs. 3-5. 

 Acmcea cingulata, Hutton : New Zeal. Journ. Sci., vol. i, 1883, p. 477; 

 Trans. N. Zeal. Inst., vol. xvi, 1883 (1884), p. 215 ; Proc. Linn. 

 Soc. N.S. Wales, voL ix, 1884 (1885), p. 372 ; Pilsbry, Man. 

 Conch. (1), vol. xiii, p. 53; Hutton, Index Faunce Nov. Zeal., 

 p. 85. 

 Shell oval, conoidal, moderately solid, white to yellowish brown, 

 with numerous radiating ribs, which are low, rounded, and varying 

 in number from 30 to 50; there are usually 10 to 15 primary ribs 

 and numerous finer riblets in the interstices ; a number of concentric 

 ridges sometimes render the ribs slightly crenate. Colour mostly 

 white, sometimes light brown, the ribs nearly white. Apex at the 

 anterior fourth, oval in shape and convex, mostly dark brown ; 

 anterior slope nearly straight. Inside white, porcellanous, central 

 area white, rarely with a small brown spot underneath the apex ; 

 margin indistinctly crenulato, with a narrow pinkish border. 

 Length 17, breadth 13, height 6 mm. 

 n 16, „ 12, „ 5 „ 

 The dentition was described and figured by Hutton (Trans. N. Zeal. 

 Inst., vol. xvi, p. 215, pi. xi, fig. 5), and a copy of his figure is here 

 reproduced. It is typical, resembling very much that of A. mitra, 

 Esch., with short, stout, conical cutting-points. 

 Type in the Canterbury Museum, Christchurch. 

 JIab. —Duneclin and Lyttelton (Hutton) ; Lyall Bay (H. S.) ; East 

 Cape lighthouse. On rocks between tide-marks, not common. 



Distinguished from its nearest ally, A. riihiginosa, by the more 

 anterior apex, the more numerous and lower ribs, the white interior, 

 and the purplish or pinkish border. Always covered with a thick 

 layer of Nulliporites. 



3. AoM^A INTERMEDIA, n.sp. PI. XXVII, Figs. 6-8. 

 Shell oval to subcircular, conoidal, thin, light brown, finely ribbed. 

 The fine, equidistant, and equal rounded riblets number from 25 to 

 50, interstitial riblets are mostly absent ; a few concentric distinct 

 growth-lines are commonly present. Colour light brown, the riblets 

 white. Apex at about the anterior third, near the centre in subcircular 

 examples; nucleus very small, oval, dark brown. Inside shining, 

 with the spatula dark brown, the border much lighter in colour. 

 Length 7-5, breadth 6, height 2-25 mm. (type). 

 „ 11, „ 9, „ 4-5 „ 



), 8, ,, 6*5, ,, 3 ,, 



The dentition is unknown. None of the specimens contained the 

 animal. Type in my collection. 



