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In land snails real sinistrality is frequent: there are families, genera, and species in which all shells are sinistral. In
some usually dextral species hereditary mutation in a population caused sinistrality of a local race: so all specimens of
Fruticicola lantzi are sinistral in one valley east of Alma Ata while this species is dextral in all other places of Central
Asia. (Schilder 1952, Biotaxonomie (Jena), p. 74, map fig. 36). In other cases, sinistral shells may be classified as rare
abnormalities: so in Helix pomatia, a large edible snail sold in large quantities chiefly in France, there is one sinistral
specimen (called "king") among 6,000 to 8,000 shells, and in the allied smaller species of Cepaea there is one sinistral
shell among 30,000 to 150,000 dextral ones (Schilder 1953, Die Banderschnecken (Jena), p. 17).
In marine gastropods sinistral shells seem to be rarer. A normally sinistral cone (Conus adversarius) from the Pliocene beds
of Florida, has been figured in the Sean Raynon Sabado (n.s.) 2:3 (February, 1960).
In cowries sinistral specimens are extremely rare, if indeed they occur at all. Among the more than 150,000 cowries which the
writer has examined personally during forty-four years special study, there was no sinistral shell. But R. J. Griffiths
(1962, Mem. Nat. Mus. Melbourne, 25:217) mentions a sinistral Notocypraea declivis which is preserved in the South Australian
Museum: its curator would oblige many malacologists if he would publish an enlarged photograph, at least of the basal view of
this curiosity.
Another case of sinistrality in cowries has been proved to be erroneous: Stoliczka (1867, Palaeont. Indica (5) 2:56, pl. 4,
fig. 6) has established a Cypraea anomala from the Cretaceous of India, believing it to be a sinistral shell. But details of
the drawing of the incomplete shell undoubtedly show that Stoliczka's specimen represents its posterior extremity, and not
its anterior extremity as the author supposed, so that anomala is a normally dextral Palaeocypraea (Schilder 1926, Rec. Geol.
Surv. India 58(4):372).
Collectors should be eager to find a really sinistral cowry among the shells which go through their hands, and if they were
happy enough to detect one, they should publish it in the Sean Raynon Sabado, accompanied by a photograph. For such a shell
would be more valuable than the rarest cowry species we know.
But I think that nobody will find a sinistral cowry.
Three small oblong cowries which have been dredged as dead shells in 80 fathoms off the Bonin Islands, have been described as
Erosaria cernica ogasawarensis Schilder 1944 (Arkiv for Zoologi 36.A.2, p. 22); their formulae i.e. length in mm., breadth
in per cent of length (in brackets [parentheses]), and number of labial and true columellar teeth (separated by a colon) are
as follows:
13(60)18:14 (a rather worn paratype), 15(57)17:15 (holotype according to Schilder 1958, Arch. Mollusk. 87:172), 16(56)19:18
(paratype in coll. Schilder No. 7433).
As these shells never have been figured before, I think it useful to publish a photograph of the last-named paratype of 16mm
because a specimen from the Bonin Is. figured by Cate (1960, Veliger 3, pl. 1, fig. 5) is a much larger and broader shell, as
its formula is 29(64)23:24.
It should be the Malacological trend to consolidate nomenclature and not separate, and separation should be done only if the
characteristics of the new species or subspecies are constant in large series (not 16 shells) of shells, and peculiar to the
new subspecies only. This does not apply at all in the case of C. chinensis amiges and the situation of tagging a new name to
every ecological variation, is getting ridiculous. I am convinced that my article will not stop Mr. Cate from naming another
dozen new subspecies before giving up his malacological hobby, however, it is only fair, that if we have to read Cate's
inconclusive arguments in favor of his new subspecies, we should be permitted to express our own arguments against accepting
his new subspecies. Furthermore, it stimulates scientific thinking, and will show to Mr. Cate that we do not accept every
subspecies he dishes out from his conveyor belt.
In The Veliger, Vol. 5, No. 2, pp. 74 77, Crawford Cate made an attempt to restore the old subspecific name amiges to current
usage. It is unfortunate that he based his differentiating comparison on specimens from the Philippines only, and did not
take into account specimens of C. chinensis (which the Schilders call C. chinensis variolaria Lamarck, 1810) from Mauritius.
The morphological relationship, despite the greater distance from Philippines, is closer by far between variolaria
(Mauritius) and amiges (Philippines), then it is between C. chinensis, sensu stricto (Philippines) and amiges.
As Crawford Cate pointed out in his article, Melvill & Standen's specimen of amiges was a single, dead shell of unknown
locality. Melvill and Standen's contention that amiges could have come from the Philippines Archipelago was a mere
presumption and by no means zoogeographical reasoning, for the specimen could have just as well come from Mauritius. Once the
locality of a holotype of a species or subspecies is unknown, it is useless to guess where its origin might have been.
The Schilders in their nomenclatural system accept (4) races or subspecies of C. chinensis, which are as follows: C.
chinensis chinensis Gmelin, 1791, (32/61, 17:16). C. chinensis violacea Rous, 1905 (31/63, 15:15), C. chinensis variolaria
Lamarck, 1810 (32/64, 15.16), and C. chinensis sydneyensis Schilder & Schilder, 1938 (35/63, 15:14). The figures in brackets
signify the following: Length in mm., width as a % of length, mean number of labial teeth as reduced to a shell 25mm. in
length: mean number of columellar teeth also reduced (see Schilder, Zool. Anz. Bd. 92, H. 3/4, 1930). The Schilders'
statistical figures were obtained by personally examining 250 specimens of C. chinensis from different localities.
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