y 
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4 
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: 
Mr. W. H. Benson on Ianthina, Bolten. 407 
sailed through a sea occupied by a large violet-blue species 
which varied in form, surface, and colour from the one named 
Lanthina ceruleata by Reeve, towards that which he has figured 
under the name of J. grandis, the spire increasing gradually in 
elevation. Larger specimens than those which I took were got 
by my companions, and still larger shells were missed by my 
casting net, or were passed while it was thrown after other ob- 
jects. Associated with this fine Janthina were the curious slaty- 
blue Lepas fascicularis, Darwin, radiating from a common 
spongy float, and furnished with coriaceous instead of testaceous 
armour; great numbers of a small blue swimming crab, using 
the free floats of the Ianthine as rafts, from which they darted 
on their prey, and returned to feed on it; a large kind of Jan- 
thina exigua, and the little pale variety of I. pallida. The tract 
in question is about midway between Natal and Swan River. 
Another species was a solitary shell taken west of the Island 
of Sumatra, about a degree north of the equator, and between 
90° and 91° of east longitude. It appears to be a small variety 
of Mérch’s Janthina Carpenteri, figured in the ‘Iconica’ as 
I. fragilis. I omitted to take a note of the animal or of its 
float. * 
Between the neighbourhood of Madeira and the Sand Heads, 
at the mouth of the river Hooghly, I recorded the capture of 
Tanthine on thirty-five days. On one occasion attempts were 
made to secure I. pallida, but without success ; and we passed large 
specimens of it on a Sunday. On two other Sundays, we ob- 
served large Janthine which could not be identified in the water, 
nor guessed at, from their not appearing on the preceding or 
following days. Including Hyalea, Creseis, Cuvieria, Cleodora, 
Atlanta, Oxygyrus, Carinaria, Argonauta, &c., shells entered our 
nets on sixty-seven days; and captures of small marine animals 
of some kind or other were made on seventy-five days,—a toler- 
able proof of the abundant employment afforded in a sailing 
voyage for a naturalist provided with suitable apparatus, when 
the numerous days on which, from various circumstances, nets 
were not used, are taken into consideration. Rapid progress 
and rough weather often prevented any attempt at fishing for 
several consecutive days, especially in the regions of the Trade- 
winds, and in the strong westerly gale which prevailed near the 
40th degree of south latitude. 
_ Reeve inadvertently states that the Atlantic and Pacific Oceans 
lay claim to all the Janthine that have been actually captured. 
The first species figured by him is, however, assigned to the Ni- 
cobar group in the Bay of Bengal ; and his I. Africana is referred 
to Zanzibar, on the African shore of the Indian Ocean. Locali- 
ties mentioned by Chemnitz and Krauss would also have helped 
* 
