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PACIFIC SCIENCE, VoL XXI, October 1967 
note the spire. We think that it is distinct. Most 
of our specimens were received labelled O. faba 
Marrat 1867, a name which we now place in 
the synonymy. 
Oliva sidelia Duclos 1835. Monogr. Oliva , pi. 
19, figs. 1, 2. Duclos (1844, p. 23, pi. 21, 
figs. 1, 2). Ducros (1857, p. 69). Marrat 
(1871, pi. 15, figs. 231, 232) (a copy of 
the figures of Duclos). Tryon (1883, pi. 
33, figs. 27, 44) (a copy of the figures of 
Duclos) . 
Tryon (1883) united, under the name O. 
sidelia, O. volvaroides Duclos 1835, O. lepida 
Duclos 1835, and O. tod osina Duclos 1835. We 
share his opinion for sidelia, volvaroides, lepida, 
and todosina, but it is our opinion that athenia, 
mucronata, and faba constitute a distinct species, 
more squat, with a more depressed spire, and 
closely mucronated in the middle. The pattern 
is much plainer and darker. Finally, sidelia, vol- 
varoides, lepida, and todosina have the last 
whorl separated by a suture greatly canaliculated, 
while in athenia, mucronata, and faba the suture 
of the last whorl is deep but very tight. We find 
ourselves presented with two distinct species, 
sidelia and athenia. It is to be regretted that the 
name sidelia, which was created for a young 
shell, should have been selected for this species. 
O. volvaroides, O. lepida, and O. todosina ap- 
ply to adult specimens. The type of O. sidelia 
is a shell 10 mm in length, white, with faint 
violet undulations, and having on the dorsal re- 
gion a large brown spot which occupies nearly 
the whole length of the last whorl, except for 
a white zone close below the suture. This 
coloration must be infrequent, since Marrat 
(1871) and Tryon (1883) copied the figures 
of Duclos. Weinkauff (1878) gave three figures 
of O. sidelia, but this interpretation is difficult, 
the author admitting that they are not elongated 
enough, and that the relation between the height 
and width is not exact. Reeve (1850, pi. 22, 
sp. 59) figured and described O. volvaroides. 
Specimens from China, Mauritius, Seychelles, 
Solomon Islands, and other localities indicate 
a distribution throughout the Indo-Pacific. A 
few forms of this species follow. 
lepida Duclos 1835. Monogr. Oliva, pi. 25, 
figs. 15 to 20. 
The shell has a pattern of triangular spots. We 
have specimens that may fit this form from 
Mauritius, Seychelles, China, and the Philip- 
pines. 
todosina Duclos 1835. Monogr. Oliva, pi. 
25, figs. 9, 10. 
This form was based by Duclos on a shell of 
which the pattern and especially the middle 
band of the last whorl are darker. The habitat 
of California indicated by Duclos is certainly 
erroneous. 
volvaroides Duclos 1835. Monogr. Oliva, pi. 
25, figs. 11 to 14. 
The type of O. volvaroides represented by 
Duclos (pi. 25, figs. 11 and 12) is coffee-and- 
cream colored with some transverse lines hardly 
visible. His Figure 13 is of a variety entirely 
white, and Figure 14 is of a uniform blackish 
brown which is so similar to Figure 20 (in- 
scribed as a variety of lepida ) that one might 
be tempted to believe that these two figures 
were made from the same shell. While main- 
taining O. volvaroides as a species, Ducros 
(1844) said that a study of a great number of 
individuals from diverse localities might au- 
thorize a reunion with O. lepida. 
Oliva tessellata Lamarck 1811. Ann. Mus. Hist. 
Nat. 16: 320, b. 28. 
The shell is yellow, spotted with purple. The 
aperture and columella are deep violet. 
Dillwyn (1817) and Marrat (1871) took 
the name O. tigrina (Meuschen 1787) for this 
species. Meuschen’s names have been declared 
invalid by the International Commission, but 
in any event it is an obvious error because no 
reference cited in the Museum Geversianum re- 
lates to O. tessellata. 
O. tessellata varies only in the number of 
punctations with which the surface is orna- 
mented. In adult specimens they deviate rarely 
on the end of the last whorl. The dark purple 
of the interior is constant. 
Some authors place this in the genus Neo- 
cylindrus Fischer 1883, with O. tessellata La- 
marck as the type. 
This is a common species distributed through- 
out the Indo-Pacific. 
