The Atoll of Funafuti, Ellice group : its zoology, botany, ethnology and general structure based on collections made by Charles Hedley of the Australian Museum, Sydney, N.S.W.
In the year 1897, a second, and in 1898, a third expedition visited the Atoll of Funafuti in prosecution of the attempt to carry a bore through the coral formation. The mollusca herein described were obtained by these parties, chiefly by deep dredging, and were remitted to the Australian Museum by the Local Funafuti Committee of the Royal Society. This material reached the Writer too late for incorporation in the body of this Memoir. The results of a study of it are accordingly presented in this appendix.
This material is of importance since it illustrates a side of the Funafuti zoology which I had little opportunity of investigating personally, viz., that of the deeper water. Dredgings carried out by Mr. G. H. Halligan in one hundred and fifty fathoms, and again in two hundred fathoms, produced results of especial interest. In the latter depth he discovered a bed of the typical "Pteropod Ooze." The sample of his dredgings submitted to me, might have stood for the portrait of that deposit figured by Murray and Renard.*
This ooze has been chiefly studied in the Atlantic, and though its equal distribution in the Pacific is a matter of course, the present record is an interesting extension of the known range.
But the chief claim that this deposit has on our attention is that it appears in water of less depth than in any instance known heretofore. The least depth in which the "Challenger" obtained Pteropod Ooze was in 390 fathoms, the greatest 1,525 fathoms, the average being 1,044 fathoms, †
The following species already noted as from surface waters again occurred in greater depths:
Teinostoma tricarinatum—150 fathoms off Beacon Islet (Funamanu), and 36 fathoms north of Pava Islet.
Cisonella ovata—150 fathoms off Beacon Islet (Funamanu).
Stomatella sanguinea—36 fathoms N. 30° West of Pava, 45 - 52 fathoms off Tutaga Islet.page 550
Cæcum vertebrale—off Tutaga in 45-52, 50-60, and 200 fathoms; off Beacon Islet (Funamanu), at 150; and in 36 fathoms north; and 36 fathoms N. 30° W. of Pava. This is evidently from its abundance a native of the deeper water. Some of the examples from 150 and 200 fathoms have a few brown blotches on the shell.
Cæcum gulosum—dredged at every station with C, vertebrale.
Columbella varians—36 fathoms N. 30° W. of Pava.
Marginella iota—36 fathoms N. 30° W. of Pava, off Beacon Islet (Funamanu) in 150, and off Tutaga in 45—52 and 200 fathoms.
Marginella sandwicensis—150 fathoms off Beacon Islet (Funamanu).
Olivella simplex—36 fathoms N. of Pava.
Those species which are either new to science or have not been yet recorded from Funafuti are as under.
* Murray and Renard—Chall. E-ep., Deep Sea Deposits, 1891, pl. xi. fig. 6.
† Murray and Renard—lac, cit., p. 225.