Oliver. — Mollusca of the Kermadec Islands. 513 



the apex, thus leaving 3 leading ridges on each side of the apex dark 

 yellowish-green. In addition to the broad bands, there are in the interstices 

 between the ribs numerous narrow reddish-brown streaks leading from the 

 margin towards the apex (seen on holding shell to light in both light and 

 dark areas). Interior iridescent slaty blue, spatula brown. 



Length, 42-5 mm. Breadth, 34-8 mm. Height, 10-3 mm. 



Variations from Type. — The ridges vary somewhat in height and regu- 

 larity, and specimens in which they are almost obsolete approach those 

 of C. craticulatus prolixus and C. vulcanicus. The normal number is ap- 

 parently 22, though usually more can be counted. The colour-pattern 

 dividing the shell into 22 areas is characteristic of this species. Some New 

 Zealand species exhibit similar pattern. A perfectly regular specimen of 

 C. hedleyi shows the central anterior ridge light-coloured, the central 

 posterior ridge dark-coloured. On each side between these the order from 

 the anterior end is dark, light, dark, 3 light, dark, light, dark, light — thus 

 making 22 in all. In old specimens the external surface of the shell is usually 

 corroded and more or less whitish in colour ; the anterior, too, is whitish, 

 with the margin clearly showing the ends of the numerous dark streaks. 



Length, 45*8 mm. Breadth, 37*5 mm. Height, 14-2 mm. 

 ,, 37-5 mm. „ 28-7 mm. „ 9-3 mm. 



,, 27-5 mm. ,, 21-6 mm. ,, 5-7 mm. 



Habitat. — Living on rocks between tide-marks, Sunday Island. This 

 is the most common limpet on Sunday Island, and occurs generally just 

 above low-tide mark. 



Subsp. corrugata n. subsp. Figs. 3 and 3a. 



Description of Type Specimen. — Shell moderately high, height 0-32 of 

 length, oval, narrowed and truncated in front. Apex in the anterior third. 

 Anterior and posterior slopes convex. Margin irregularly dentate. Sculp- 

 ture : There are about 27 high angular ridges of varying heights, each 

 bearing 2 to 5 beaded ribs. A beaded rib often in the interstices. Colour : 

 Above dark yellowish-green, becoming paler towards the centre. Interior 

 iridescent slaty blue, central portion white. Dark colour-streaks (one in 

 nearly every interstice seen on holding shell to light) reddish-brown, narrow, 

 mostly continuous from near apex to margin. 



Length, 38 mm. Breadth, 32-3 mm. Height, 12 mm. 



Variations from Type. — Measurements : — 



Length, 42-8 mm. Breadth, 370 mm. Height, 11-3 mm. 



47-8 mm. „ 42"0 mm. „ 17 mm. 



,, 38-8 mm. ,, 31-6 mm. ,, 15-8 mm. 



Habitat. — Common living on rocks between tide-marks, Macauley Island, 

 and the only Cellana collected there. I have also one specimen from 

 Sunday Island. 



Cellana vulcanicus n. sp. Figs. 4 and 4a. 



Recorded, Iredale, Pro. Mai. Soc, ix, 71, 1910 (Helcioniscus dirus). 



Description of Type Specimen. — Shell high, height 0-42 of length, elliptical, 

 slightly narrowed in front. Apex more than a third of the length from 

 the anterior end. Anterior slope steep, nearly straight ; posterior slightly 

 convex. Margin finely crenulate. Sculpture : There are about 60 well- 

 marked radiating ribs, alternately high and low, crossed by concentric 

 growth-lines, giving a beaded appearance, The apex is corroded. Colour : 



17— Trans. 



