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Shell component
Let me prove this accusation by discussing the variation in size of Cypraea tigris in Fiji. In The Cowry (1:3, p. 43, 1962)
F. A. Schilder has stated the average length of tigris from Fiji and Tonga as 76 mm. In The Cowry (1:5, p. 74, 1963) W.O.
Cernohorsky writes: "Every Fijian collector has a specimen of tigris from 105 mm to 110 mm...I have seen nearly 25 specimens
of tigris approaching 110 mm... From personal observations and measurements I place the mean length of C. tigris from Fiji as
about 90 mm." Let us see how this difference can be explained, and which indication is correct.
Apparently W.O. Cernohorsky fears that research workers may be led astray by only using shells from a single locality of a
region and he tells us that with some populations in Fiji, all shells are "dwarf" size. In others (especially Vatia Wharf)
all shells are "giant" size. As Mr. Cernohorsky has collected for us in a most generous way with thousands of Cypraeidae
(mostly with the animal within) from many localities all over Fiji, we base our research of Fijian shells mostly on the
specimens collected by him. In addition, Mr. Cernohorsky often provides us with the results of his own measurements of other
specimens. He told us that his maximum tigris from Vatia Wharf is 92 mm long.
We measure each shell with calipers in tenths of millimeters and get our means from each series of each locality. The
following table indicates
(1) the number of specimens,
(2) the exact locality,
(3) the length (in classes of 5 mm: 65 = 63 - 67, 70 = 68 - 72, etc.), and
(4) the mean of the length in mm.
The mean of the 7 means of population is 78, as well as the mean of all 93 specimens coming from these localities. The mean
indicated in The Cowry (1:3) was 76 instead of 78, as other sources were used there too, shells from museums, from the study
of Dr. A. Kay in The Veliger (4:1, p. 36, 1961) and shells from Tonga. But the mean of tigris from Fiji can never be 90 mm as
W.O. Cernohorsky suggested
The last two lines of the table refer to the 24 females and 33 males examined from all Fijian localities (except Vatulele
Is., where only dead shells have been collected): therefore the mean of the sum of 57 live specimens is a little higher (79
mm) than that of all 93 specimens. The difference between the average size of females (81 mm) and males (78 mm) agrees with
that observed in most other species of Cypraeidae: the average size of males is only about nine tenths of that of the females
(see The Cowry 1:4, p. 50, 1962).
The average length of shells can be approximately estimated by halving the sum of the minimum and the maximum known. As our
tigris from Fiji vary from 60 to 92 mm, the estimated mean is 76 mm, which figure rather approaches the mean size 78 mm
calculated above. This rule, however, can only be adopted for shells coming from a restricted area or at least belonging to
the same geographical race. It does not fit the tigris coming from the whole Indo-Pacific: the mean of the two extremes (44
mm measured by F.A. Schilder, 1930, in coll. Vayssière in Marseilles, and 147 mm mentioned by A. Kay, 1961) is 95 mm; it is a
far too large figure, as it is influenced by the Philippines local race schilderiana Cate (80-147 mm, estimated mean 114 mm),
while typical tigris from the vast area from East Africa to Polynesia are much smaller (44-112mm estimated mean 78 mm). The
latter figure agrees with the calculated mean of the specimens from Fiji.
Four curious Cypraea tigris Linnaeus, which are preserved in my collection (CS.), have been photographed by Miss Lydia Klotz,
Zoological Institute of the University Halle Germany; these photographs may encourage conchologists to collect similar
deformations.
Fig. 1 represents a specimen of 74 mm. (CS. No. 3017) in which the outer lip has been broken off; the labial teeth have been
rudimentarily restored, but on a more upward edge of the right wall, so that it became necessary to construct a second row of
columellar teeth anteriorly.
Figs. 2 and 3 show a shell of 69 mm. (CS. No. 3019) with the outer lip enormously thickened so that the right margin
protrudes in a roof-like manner and the labial teeth become rather obsolete.
Figs. 4 and 5 exhibit a shell of 85 mm. (CS. No. 3020) the outer lip of which has been constricted behind in a curious way;
these features may be caused from a healed break caused by a fish bite when the shell was still thin, but it also may be
interpreted as the beginning formation of a second posterior outlet comparable to that observed in many Amphiperatidae.
Figs. 6 and 7 show a heavy shell of 88 mm. (CS. No. 840) in which the dorsum is suffused by a layer of dirty enamel
containing many particles of mud; this layer is so thick that it almost hides the dorsal markings, and forms a distinct
dorsal sulcus the entire length of the shell; the anterior extremity is enlarged by thick layers of greenish enamel which
look like a covering on a barnacle.
The three first-named shells have been selected among several thousand Cypraea tigris amassed in the cellar of the curio shop
Umlauff (Hamburg) in 1928; no locality was given. The last-named shell was bought from the dealer, H. Rolle, of Berlin in
1924: it is said to come from New Caledonia, but as "rostrate" cowries mostly have been reported from there, I distrust the
reliability of this locality.
Bernaya teulerei Cazenavette is a relic of a genus common in lower Tertiary beds from the Mediterranean Basin to India; this
relic is a rare species, as only about 35 specimens are preserved in all public and private collections in Europe. It is
allied to the South African Bernaya fultoni Sowerby (see Sean Raynon Sabado, n.s. 51:2), but differs by the white teeth
becoming obsolete: there are barely discernible traces of labial teeth, and the inner lip is quite smooth (see fig. 1 above);
the dorsum shows a healed wound caused probably from the bite of a fish.
Cazenavette (1846, Act. Soc. Linn. Bordeaux 14:117) described teulerei as coming from the Persian Gulf, but later expeditions
to this region failed to find this rather large species again, so that the correctness of the habitat became doubtful.
Moreover the term "Persian Gulf" was often misused in those days to conceal the lack of the known habitat. Three years
earlier, Gaskoin (1843, Proc. Zool. Soc. London 11:25) had described the same species by the preoccupied name leucostoma
after nine specimen shells received from Mocha: but as later expeditions also failed to find this species among the well
known fauna of the Red Sea, the habitat Mocha also seemed unreliable, as Mocha was a market place where curiosities coming
from everywhere were offered. Therefore the true habitat of teulerei seemed uncertain.
However, a century later both indications proved to be correct. In 1934 teulerei was collected alive in the Hormuz Strait
(Schilder 1960, Arch. Mollusk. 89:185), and R. C. Spence found "hidalgoi Shaw" (which is a later synonym of the species) in
the Red Sea (Haw. Shell News, n.s. 8:6, 1960). According to personal communication by Mr. Spence, he collected one live
specimen on the coral reef a mile off Port Sudan.
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