Fintay.—New Zealand Calliostomidae. 103 
a prominent cancellated appearance to the shell. There are four of these 
spirals on each whorl, with no interstitials, but the lowest is weakened an 
on the spire-whorls hidden by the whorl below, so that these whorls have 
only three spirals. Axials, though strong, only half the width of spirals, 
straight between suture and rib above and below it, but decidedly sloping 
backwards elsewhere, forming laterally compressed nodules at intersections 
with spirals, those on lowest rib of body-whorl smaller but equal in 
number to those on upper ribs., Base with one very prominent moniliform 
rib just inside periphery, then a totally smooth concave space, then four 
nodulous umbilical ribs, the inner two being much closer and finer, but, 
as body-whorl is missing, this:is probably not the true basal sculpture. 
Suture rendered false-canaliculate by the prominence of the spirals. Sides 
of aperture thick, columella less oblique than in C. suteri, little reflexed, 
"but with a rather prominent basal notch. 
Height (estimated), 10mm. ; width, 6mm. (Imperfect holotype.) 
Holotype, from Ardgowan, in the author's collection. 
Calliostoma marwicki n. sp. (Plate 10, fig. 4.) 
1918. Basilissa n. sp. (Sut.), N.Z. Geol. Surv. Bull. No. 20, р. 90. 
Shell fairly solid, acutely conical, imperforate. Protoconch lost in 
the unique specimen; first remaining whorl with tw i 
next whorl becomes another spiral rib almost equal in size to the lower 
two; all the ribs strongly nodulous. At the same ti 
connect nodules. The main ribs continue subequal in size, but later on a 
thin interstitial riblet is intercalated between each pair, axials become 
5 mm. 
Holotype, from Ardgowan, in the collection of the New Zealand Geo- 
logical Survey. 
Remarks.—This shell is an extreme form of Calliostoma, апа approaches 
certain sections of Cantharidus. Mr. Marwick mentions (in litteris) that 
this is the second Basilissa sp. of Park’s Ardgowan list, and that the 
basal ornamentation shows it is a close ally of C. cancellatum (vide ante), 
though the spire sculpture is very different. 
e author's thanks are due to Mr. P. G. Morgan and Mr. Marwick 
for permission to describe this shell, and it is named in honour of the 
latter gentleman, whose help and criticism have been invaluable. 
