456 Transactions. 
bearing distinct parietal plait, but only very indistinct traces of tubercles 
elow. 
Height, 17 mm.; diameter, 10 mm. 
Holotype (unique), from Kakanui Beach (tuffs below the limestone), 
Cymatium revolutum n. sp. (Plate 51, figs. 2a, 2b.) : 
Shell rather small, ovate; spire very little distorted by varices, whie 
occur at intervals of less than three-quarters of a whorl. Whorls regularly 
rounded, no prominent carinae or nodules. Apex, canal, and outer lip 
missing in all specimens. About 14 narrowly convex spiral cords on body- 
whorl, 5 or 6 on penultimate, interstices 2-3 times their width, with 1-4 
very fine interstitial riblets; less prominent vertical axial ribs (12-15 
between varices) cancellate the spirals, raised at intersections into sm 
sharp tubercles. Extremely fine and close secondary axial sculpture reticu- 
lates interstitial spiral riblets. Varices not very much wider or more pro- 
minent than axial ribs, but less tuberculose, and slant in different direction. 
Height (estimated), 16 mm. ; diameter, 9 mm. (type— juvenile). Ў 
The largest paratype. of which only three anterior whorls remain, 1$ 
axials in comparison with the spirals. It is also from a higher horizon. for 
it may be noted that the ** Turbo marshalli fauna" of the Kakanui айз 18 
identical with that from the true Waiarekan tuffs—a significant fact, whic 
will be discussed on another occasion. | 
Cymatium marwicki n. sp. (Plate 51, figs. la, 1b.) 
Shell rather small, fusiform, very little distorted by varices, which occur 
at intervals of almost three-quarters of a whorl ; 31 post-embryonic whorls, 
convex outlines. Protoconch apparently large, initial whorls missing, final 2. 
volution with 4 faint ridges, the upper and lower much more prominent, à 
t break (but no varix) marks it off from true sc | 
on early whorls of 6 low, subequidistant, spiral keels, the lowest glose 00, . 
the uppermost margining the suture. On later whorls the three upper cords 
always remain much weaker than the others, of which peripheral one becomes 
strongest, those below on body-whorl gradually falling away in strength. _ 
» " 
Six cords below peripheral one present on body-whorl down to end of outer- 
| weaker alternating. Interstices between the three main co 
lip varix, below this are about 10 more on neck of canal, stronger ai 
rds occupied 
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