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the figures in PI. XL VI., in some of which the aperture is a simple marginal fissure, like 
that of Textularia (proper), in others a bordered slit, either close to the margin or removed 
some distance from it, whilst in a few it appears as a bordered or tubulated orifice, still 
further displaced so as to be nearly central. In the present state of our knowledge there 
is little to be gained, either in precision or convenience, by placing in a separate genus the 
few variable and comparatively unimportant forms which present, in a greater or less 
degree, the latter peculiarity. 
The minute structure of the test in Gaudryina exhibits nearly the same range of 
characters as that of the typical Textularice. The walls are seldom really hyaline or 
distinctly perforated, though in some species they are thin, homogeneous, and quite 
smooth ; whilst in others they are thick, opaque, and calcareous, and in the remainder, 
more or less coarsely arenaceous, and rough externally. 
The geographical distribution of the genus is world- wide. Its geological history 
commences with the Cretaceous period, when it was tolerably abundant, and is continued 
in various Tertiary formations down to recent times. 
Gaudryina pupoides, d’Orbigny (PI. XLYI. figs. 1-4). 
Gaudryina pupoides, d’Orbigny, 1840, Mem. Soc. geol. France, vol. iv. p. 44, pi. iv. figs. 22-24. 
,, „ Id. 1846, For. Foss. Vien., p. 197, pi. xxi. figs. 34-36. 
,, subglabra, Giimbel, 1868, Abb. d. k. bayer Akad. Wiss.,II. Cl., vol. x. p. 602, pi. i. fig. 4. 
Gaudryina pupoides is an easily recognised species. Its dimorphous mode of growth 
is generally very apparent, and its variability is limited to such features as the number 
of segments, the relative length and breadth of the test, and the degree of lateral 
compression. In recent shells the walls are thin and calcareous, smooth externally, and 
almost invariably of a greyish hue; fossil specimens sometimes exhibit a slightly rough 
exterior. In form and position the aperture resembles that of the typical Textularice, 
but it is often surrounded by a raised lip or border. 
Gaudryina pupoides is a common deep-water Poraminifer. The list of localities 
at which it has been found includes fourteen Stations in the North Atlantic, the most 
northerly being in about lat. 60° N., the depths ranging from 173 to 1780 fathoms; 
five Stations in the South Atlantic, 350 to 2350 fathoms; sixteen in the South Pacific, 
129 to 2425 fathoms; and two in the North Pacific, 1850 fathoms and 2050 fathoms 
respectively. 
In the fossil condition it is chiefly known as a Cretaceous species. The localities 
originally given by d’Orbigny were the Chalk of Meudon, Sens, St. Germain, and England; 
and to these Reuss has added various districts situated on the Chalk and Gault of 
North Germany. The Gaudryina subglabra of Giimbel, which may be referred to the 
same species, occurs in the Eocene formation of the Bavarian Alps. 
