REPORT ON THE FORAMINIFERA. 
433 
Ehrenbergina , Beuss. 
Cassidulina , pars, d’Orbigny [1839], Carpenter, Parker and Jones. 
Ehrenbergina , Reuss [1849], Karrer, Parker and Jones, Brady. 
The typical form of the test in the genus Ehrenbergina may be compared to that 
of a Cassidulina i which has been opened out and partially or entirely unrolled. The 
shell is broad at the distal end, and the regular Textularian arrangement of the segments 
is distinctly shown, especially on the convex or dorsal face ; the ventral face is more 
or less concave. In well-marked specimens the lateral margins are thin and often serrate ; 
but occasionally they are obtuse and rounded, and in such cases the form of the test 
approximates to that of the true Cassidulince. 
The distinction between Ehrenbergina and the elongated varieties of Cassidulina 
is by no means strongly defined. It rests chiefly on the fact that in Ehrenbergina 
the line of segments appears to be unfolded laterally as well as uncoiled vertically, and 
that the segments are inequilateral, differing in form on the ventral and dorsal faces 
of the test. 
Geographically the occurrence of living Ehrenbergince is almost confined to the 
southern hemisphere, though specimens have been found at one or two points in the 
tropical part of the North Atlantic, and at a single Station in the North Pacific. The 
genus is tolerably common both in the South At] antic and in the South Pacific, and 
has a very wide bathymetrical range. The only known fossil representatives are rare 
specimens of Miocene age from the neighbourhood of Vienna. 
Ehrenbergina pupa, d’Orbigny, sp. (PI. LV. fig. 1 , a.b., PI. CXIII. fig. 10, a.b.c.). 
Cassididina papa, d’Orbigny, 1839, Foram. Amer. Merid., p. 57, pi. vii, figs. 21-23. 
This is the simplest exemplification of the generic characters, and its affinity to the 
typical Cassididince is easily recognised. It differs from its congeners in the even or 
slightly lobulated condition of the lateral edges, and in the entire absence of sharp angles 
or spines. 
Ehrenbergina pupa is a comparatively rare species, and with the exception of a single 
locality in the North Atlantic — off the Azores, 450 fathoms — has only been found on 
the shores of South America. D’Orbigny’s original specimens were obtained from the 
Falkland Islands, and it is a matter of some interest that it has again been collected 
in their immediate vicinity, namely, at Station 317, depth 1035 fathoms. The remain- 
ing localities are Stations 321, mouth of Eio de la Plata, 13 fathoms; and two points 
on the west coast of Patagonia, 120 fathoms and 175 fathoms respectively. 
