REPORT ON THE FORAMINIFERA. 
170 
beset with minute pits or depressions in close, regular, parallel lines extending from one end 
of the test to the other. Test imperforate, the pitted depressions penetrating only about 
half the thickness of the shell- wall. Length, ^tli inch (l - 9 mm.). 
This is an exceedingly interesting species, both on account of the peculiar structure of 
the shell- wall and the variability of the aperture. 
The test is porcellanous and opaque, and the surface is marked by rows of pits, which 
at first sight bear considerable resemblance to perforations. The punctation, however, 
under ordinary circumstances, does not extend much beyond half the thickness of the 
shell-wall, and a transverse section of the test has the appearance represented in the 
annexed woodcut (fig. 4, e.). Occasionally, though very rarely, an old specimen may 
be met with, more or less distinctly perforate at prominent points of the surface ; but 
this condition is never found except in dead and worn shells, and it is manifestly the 
result of subsequent erosion. 
The woodcuts (fig. 4, a, b, c, cl) illustrate the variability of the aperture better than 
any verbal description. The orifice itself is usually oval, and situated in a deep depression 
with a bilabiate or cruciate border, or occasionally one of intermediate form ; but cases 
are not wanting in which the fissure follows the contour of the border, as in fig. c, and 
becomes lobulatecl at the margin. 
a b c d 
e 
Fig. i.—Miliolma rupertiana. 
a.b.c d. Various forms of aperture ; magnified 40 diam. 
e. Transverse section of the shell ; magnified 200 diam. 
The distribution of Miliolina rupertiana is limited to the shallow-water margins of 
the seas of warm latitudes. The Challenger collections only furnish specimens from the 
islands on the south shores of Papua, west of Torres Strait (Stations 186 to 189, depths 6 
to 28 fathoms), and even here the species is very rare. It occurs in material dredged by 
Mr. Haly, the zealous and energetic curator of the Colombo Museum, on the north-west 
coast of Ceylon, 2 fathoms ; in the late Mr. M'Andrew’s dredgings, in the Gulf of 
Suez, 15 to 20 fathoms; and, much more plentifully, in littoral sands collected for me 
by Mr. L. Kitching, near Tamatave, on the east coast of Madagascar. 
