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The photograph reproduced above represents the holotype of Gisortia gisortiana pterophora SCHILDER (1927) from the Middle
Eocene of northern France (Boisgeloup near Gisors); it is 26 cm. long (about 10.4 inches). The curious lateral appendices and
the dilatation of the posterior beak are absent in Gisortia gisortiana PASSY, the length of which varies from 22 to 29 cm.,
so that the unusual characters of pterophora may be interpreted as a sign of beginning degeneration. The photograph was been
made by Mr. V. J. Stanek (Prague) in 1928; an exact drawing of three views of this specimen has been published by the writer
in 1930 (Proc. Malac. Soc. London vol. 19, pl. 11, fig. 14-16). But Gisortia gisortiana is not the largest cowry: the last
representative of the group destined to become extinct is Gisortia hoernesi LEFEVRE from the Upper Eocene (Priabonian) of
northern Italy of which inner casts only are preserved: but the shell must have been at least 35 cm. long (14 inches).
There is still another group of fossil cowries which tend to gigantism, and are even more interesting to malacologists
studying living species only: for it is geologically younger than the Gisortiinae, and it is closely allied to a living group
of species . Zoila (Gigantocypraea) gigas McCOY lived in Middle Miocene (Balcombian) times (about 20 million years ago) in
about the same area (Victoria) as the recent Zoila (Zoila) thersites GASKOIN lives (south Australia), which is closely allied
to gigas so that the two species can be separated subgenerically at most. But while thersites becomes at most 92 mm. long
(coll. SUMMERS), the largest gigas measures 215 mm. (British Museum): it is a well preserved shell showing the total
reduction of columellar teeth as it is in Gisortia, too. In Zoila, the giant members with obsolete dentition also became
extinct, whereas the smaller, more denticulate species survived.
It will be observed, that the largest living cowry species, Macrocypraea cervus shows similar tendencies as the dying
Gisortia and Gigantocypraea though yet in a lesser degree: gigantism, wide aperture, flattened fossula, and irregularities in
columellar dentition. Possibly it may be the next living cowry to become extinct.
It was a somewhat frustrated group of adventurers that gathered at the jetty at Lumut on the first day of the Chinese New
Year. They included Jack Fisher, Stephen Chum, Alan and Mrs. Tideman and their rugged three year old son David plus two
aqualungs, ten large air cylinders, and other underwater equipment. Five days of holidays lay ahead, and now; the Captain had
orders that the boat could now only take us to Pankor Laut. Originally it was to have taken us to the Sembelans, a group of
nine islands, ten miles out beyond the Pankors and their silty water. This island we had thoroughly investigated last
November. Telephone calls to Telok Anson in Penang were in vain as all the Harbor officers were taking advantage of the long
holiday. It seemed that my 500 mile journey from Singapore, Jack and Stephen's 300 mile trip from Kuala Lumpar and Alan and
my family's 300 mile run down from Penang were to be virtually wasted, the next five days were to be spent going over ground
we had already covered without much success.
Recently T. A. Garrard (1963, Journ. Mall Soc. Australia 7:45, pl. 7, fig. 5-6) described Neosimnia tinctura n. sp. from
Moreton Bay. The dentate outer lip excludes it from Neosimnia or Pellasimnia (which genus replaces Neosimnia in the
Indo-Pacific) and from the subfamily Volvinae altogether; it really belongs to the other subfamily, Ovulinae, of the family
Ovulidae (which name must replace Amphiperatidae since the author of Amphiperas, (Gronow), has been declared invalid by
opinion 261 of the International Commission of Zoological Nomenclature).
The general characters of tinctura agree with Primovuia striatula Sowerby and its Eastern subspecies renovata Iredale, which
have been figured in my monograph of Amphiperatinae in 1932 (Proc. Malac. Soc. London 20:58, figs. 17 and 16 respectively),
and differ quite from Pellasimnia formicaria Sowerby and P. subreflexa Adams & Reeve with which Gerrard compared his "new
species." Primovula striatula striatula lives in the Arabian Sea, its subspecies renovata spreads from Malaysia through
Queensland to Sydney, and a third subspecies, verconis Cotton & Godfrey, has been found in South Australia and Albany (see
Schilder 1941, Archiv. Mollusk. 73:107).
The renovata from Mackay and Yeppoon as well as those from Port Jackson are purplish pink with a whitish dorsal zone, a paler
pink outer lip, and orange extremities, the tinctura from Moreton Bay, however, are fawn with the base almost fulvous, but
otherwise identical in general features (as dorsal striation and keel, dentition of the outer lip, funiculum, fossula, orange
extremities, etc.) except in size and shape: Chart by Maria Schilder
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