195 
those of presumably the same age in the Northern Hemisphere, 
see the article just mentioned. 
In addition to the forms described in this paper, there is also 
present in the material a parasitic organism of doubtful relation- 
ship. It-is not clear from the few ‘examples obtained whether 
the object belongs to the foraminifera or annelida. This is held 
over for further investigation. — 
CoRNUSPIRA SCHLUMBERGI, sp. nov. PI. x., figs. 1-3. 
Ref.—Cornuspira Schlumbergi, How., MS., Report of Fifth 
Meeting of Aus. Ass. for Adv. of Science, Adelaide, 1893, p. 366. 
Test. discoidal, flat or biconvex, convoluted ; consisting of a 
non-septate tube, slightly increasing in diameter, but with vary- 
ing dimensions. Initial end of chamber spherical, and of greater 
diameter than the tube. Convolutions, about five in number, 
more or less asymmetrical, particularly in the earlier growth. 
Test-walls investing, each successive whorl enclosing all the pre- 
ceding by alar extensions over the lateral surfaces of the shell. 
Periphery rounded, and somewhat irregular in outline. Septa- 
tion obscured exteriorly by lamination of shell-walls, except near 
the orifice, where a sutural depression is visible for about half 
the length of the final convolution. Transverse section of tube 
round, or with slight vertical compression. Aperture formed by 
the open end ue tube, more or less constricted at vent. 
Diameter, ;’5 in. 
This is an interesting species, and diverges from the normal 
characteristics of the genus in two particulars—the irregular 
coiling of the earlier convolutions of the tube, and also in the 
lamination of the test-walls. The former of these features is 
subject to considerable variation. Some transparent sections 
show but slight divergencies of the spiralline arrangement of the 
chamber from one plane, whilst in others the tube has apparently 
coiled upon itself at almost right angles, as shown in fig. 3, 
plate x. Again, unlike other members of the genus, there is a 
complete investment. of the earlier convolutions by successive 
layers of shell substance, obscuring the septation, and giving the 
shell a lenticular outline in transverse section. The irregular 
coiling of the tube in this species makes it isomorphic with 
Ammodiscus gordialis (P. & J.) in the arenaceous series. The 
duplication of the test-walls is a still more eccentric feature of 
this species. The thickening of the test in the umbilical region 
is produced, not by an excresence of shell substance, which not 
unfrequently occurs in certain species of foraminifera, but by 
an extension of the lateral flaps of the chambers in a similar 
manner to the nummulitic method of growth. This is shown 
in the transparent section, fig. 2, plate x. 
