662 
THE VOYAGE OF H.M.S. CHALLENGER. 
Miocene of Lower Bavaria (Egger), and from the later Tertiaries of Southern Italy 
(Costa), and of the Island of Rhodes (Terquem). 
Truncatulina tenuimargo, n. sp. (PI. XCIII. figs. 2, 3). 
General structure of the test similar to that of Truncatulina lobatula, from which it 
differs mainly in the extension of the peripheral borders of the segments, so as to 
form a well-defined, continuous, marginal wing or keel. Diameter, -^th inch (0‘5 mm.). 
Truncatulina tenuimargo is a small carinate modification, seldom attaining the 
average dimensions of the typical form. As in Truncatulina lobatula, the disposition of 
the convolutions varies considerably in different specimens. The variety is distinguished 
from Truncatulina culter, P. and J., which also has a carinate shell, by its comparatively 
small number of segments and the simpler construction of the test, and frequently also 
by having a depressed or excavated umbilicus. 
Out of the eight localities at which Truncatulina tenuimargo has been observed, four 
are referrible to the east coast of Australia and the neighbouring shores of New Zealand, 
depth from 38 to 1100 fathoms. The remainder are, — Torres Strait, 155 fathoms ; off the 
Ki Islands, 129 fathoms; off the Fiji Islands, 255 fathoms; and one point in the South 
Atlantic, north of the Falkland Islands, 1035 fathoms. 
Truncatulina wuellerstorji, Sch wager, sp. (PI. XCIII. figs. 8, 9). 
Anomalina wullerstorfi., Schwager, 1866, Novara-Exped., geol. Theil, vol. ii. p. 258, pi. vii. 
figs. 105, 107. 
The thin, outspread, intermediate forms connecting Truncatulina lobatula with 
Anomalina ariminensis are well typified by the Anomalina wuellerstorji of Schwager’s 
memoir. The superior face of such shells is slightly convex, the inferior nearly flat, 
and the peripheral edge acute; the chambers are narrow and much curved, often almost 
crescentiform in outline. Of the drawings, fig. 9 represents the more typical specimen. 
Truncatulina wuellerstorji is a common constituent of the deep-water ooze of all the 
great oceans. The catalogue of localities at which it has been noticed includes fifteen 
Stations in the North Atlantic, depth from 350 to 2435 fathoms; seven in the South 
Atlantic, 675 to 2350 fathoms; one in the Southern Ocean, 1570 fathoms; thirteen in 
the South Pacific, 210 to 1940 fathoms; and three in the North Pacific, 345 to 2050 
fathoms. 
The fossil specimens from which the species was originally described were found by 
Dr. Schwager in the Pliocene deposits of Kar Nicobar. 
