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THE VOYAGE OF H.M.S. CHALLENGER. 
140 fathoms ; and at seven “ Porcupine ” Stations to the west of Ireland, at depths varying 
from 85 to 1630 fathoms. It has been observed both in the Mediterranean and the 
Adriatic. In the North Pacific it has been found in shallow water at three localities, 
namely : — the Inland Sea, Japan, 15 fathoms, the Chinese Sea, and in Hong Kong Harbour, 
7 to 1 0 fathoms. In the southern hemisphere the species is exceedingly rare, nevertheless, 
it has been taken in Humboldt Bay, Papua, just south of the equator, 37 fathoms, and 
at one point in the South Atlantic, 260 fathoms. 
As a fossil its range does not extend much beyond the middle of the Tertiary epoch. 
It is found in the Miocene of the Vienna Basin, and of Malta (d’Orbigny, Parker and 
Jones); and in the later Tertiaries of North Germany (Roemer), of Italy (Costa, Terrigi, 
and others), and of Spain (Parker and Jones). 
Bigenerina digitata, d’Orbigny (PI. XLIV. figs. 19-24). 
Bigenerina ( Gernmulina) digitata , d’Orbigny, 1826, Ann. Sci. Nat., vol. vii. p. 262, No. 4. — 
Module, No. 58. 
Bigenerina digitata , Brady, 1864, Trans. Linn. Soc. Lond., vol. xxiv. p. 468, pi. xlviii. fig. 8. 
Textularia agglutinans, var. ( Bigenerina ) digitata, Parker and Jones, 1865, Phil. Trans., vol. civ. 
p. 371, pi. xvii. fig. 81. 
Bigenerina digitata, Parker, Jones, and Brady, 1865, Ann. and Mag. Nat. Hist., ser. 3, vol xvi. 
p. 28, pi. ii. fig. 61. 
The test of Bigenerina digitata is cylindrical, and tapers very gradually towards the 
aboral end, which is subconical or rounded, not compressed. The transition from the 
Textularian to the Nodosarian mode of growth is not marked by any difference in external 
contour as in the allied Bigenerina nodosaria. The walls are constructed of fine siliceous 
grains, neatly joined by means of a dark-coloured cement ; and the exterior is nearly 
smooth. The test is of rich brown hue, often lighter towards the distal end. The aper- 
ture is usually central, but sometimes it is excentric or even marginal ; its occurrence in 
the latter position was put forward by d’Orbigny as the distinctive character of his sub- 
genus’ Gernmulina. 
Bigenerina digitata is only known as a European Foraminifer. The record of its 
distribution in the living condition is limited to the eastern shores of the North 
Atlantic, and the coasts of the Mediterranean and the Adriatic. It has been dredged 
off Shetland, off the Hebrides, and at four “ Porcupine ” Stations off the west coast of 
Ireland, at depths ranging from 40 to 1230 fathoms, and in shallow water off the coast 
of Denmark. It occurs in the lagoons and littoral sands of the Adriatic, and at a depth 
of 40 fathoms in the Mediterranean. 
In the fossil state it has been observed in the later Tertiaries of Italy (Parker 
and Jones, Seguenza), and of the neighbourhood of Malaga (Parker and Jones). 
