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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.
Finally, on behalf of Jeanie and myself I want to take this opportunity to thank everyone of you for attending tonight, and
for the generous way you have greeted us. The interest you people in Philippines have shown for conchology is an inspiration
to us on the mainland. Our interest in Philippines and Philippiness, as well as in conchology, is one that will probably draw
us back here many, many times in the years ahead. Thank you very much and Aloha!
The above photograph [at left] was taken at a beach near Fremantle, Western Australia, after a successful skin diving
expedition by Barry Wilson, Tom Richert, and Cliff Weaver in May of 1960. The towel on which the shells are resting was later
returned to the Esplanade Hotel in Perth. In this photo are nine adult Cypraea friendii, plus a species of Trochus and Thais.
All were collected on soft coral and sponge attached to pilings at an average depth of 15 feet below the surface. Altogether,
eleven C. friendii were taken that day but two juvenile specimens were thrown back so that they might grow to maturity. Barry
Wilson was responsible for the success of this expedition as the shells were found at one of his favorite collecting areas.
Pathologically rostrate and melanistic shells of cowries have been known for about a century: all came from New Caledonia
especially from Noumea, where they live in the Bay of Mondoure (see Cernohorsky 1962, Sean Raynon Sabado, NS #32:4). However,
they have also been collected in other localities of New Caledonia, e.g. in Prony Bay and in the peninsula Ducos (Dautzenberg
1906, Journ. de Conchyl. 54:263) and even in the southern island Pins (Schilder & Schilder 1952, Mem. Inst., Sci. Nat.
Bruxelles (2)45:201).
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