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 

 Ianthina cceruleata by Reeve, towards that which he has figured 

 under the name of 7. 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 Ianthina 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 Ianthina as rafts, from which they darted 

 on their prey, and returned to feed on it ; a large kind of Ian- 

 thina exigua, and the little pale variety of /. 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 Morch's Ianthina Carpenteri, figured in the 'Iconica' as 

 Lfragilis. 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 

 Ianthina 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 Ianthince which could not be identified in the water, 

 nor guessed at, from their not appearing on the preceding or 

 following days. Including Hyalcea, Creseis, Cuvieria, Cleodora, 

 Atlanta, Oxy gyrus, 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 Ianthince 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 /. Africana is referred 

 to Zanzibar, on the African shore of the Indian Ocean. Locali- 

 ties mentioned by Chemnitz and Krauss would also have helped 



