618 
THE VOYAGE OF H.M.S. CHALLENGER. 
Pullenia obliquiloculata, Parker and Jones (PL LXXXIY. figs. 16-20). 
Pullenia obliquiloculata, Parker and Jones (1862, Introd. Foram., p. 183); — 1865, Phil. Trans., 
yoI. civ. p. 368, 421, pi. xix. fig. 4. 
„ „ Ponrtales, 1867, Bull. Mus. Comp. ZooL Camb. (1867), p. 107. 
„ „ Brady, 1879, Quart. Journ. Micr. Sci., vol. xix., N. S., p. 294. 
This species is only incidentally mentioned by Parker and Jones ( loc . cit .) as 
“ another form of Pullenia” which ‘ : has the chambers set on obliquely”; and though 
it is one of the most important constituents of the Globigerina ooze of tropical latitudes, 
it has passed almost unnoticed by subsequent observers. 
The test is sub globular, inequilateral, and somewhat compressed ; and its mode 
of growth irregularly nautiloid, the successive whorls not being on the same plane. 
It is larger than either of its congeners, fully-grown specimens attaining a diameter of 
about ^p-th inch (O' 8 4 mm.). The shell is composed of from two to three convolutions, of 
which the latest, consisting usually of four or five segments, is alone visible externally. 
The segments are inflated, and the sutural lines marked by slight depressions. The 
aperture is a long oval or crescentic opening on the inner margin of the final segment, 
generally obliquely set. Its superior border is rounded, owing to the turning inwards of 
the edge of the shell, as shown in the sectional drawing (fig. 20). The surface of the test 
is smooth and polished. The perforations, although larger than in Pullenia splicer oides, 
are minute as compared with those of many of the Globigerinidse. In thin sections 
of the shell they have the appearance of tubular canals of - 5 pVo th or 40 \ )0 th inch (0 - 005 
or 0'0063 mm.) diameter. 
Pullenia, obliquiloculata is the only variety of the genus which has been found living 
in the surface-water of the ocean, but that it is exclusively a pelagic species is more than 
can be affirmed from any evidence at present forthcoming. The surface-specimens, 
one of which is represented in fig. 18, a. b.,. are, as a rule, small and thin-shelled. Such 
examples have been observed amongst the tow-net organisms collected at six points in 
the Atlantic, and at seven points in the Pacific, but the number of the specimens 
collected is comparatively small. 
The distribution of the. species is best estimated from bottom-dredgings, which have 
revealed its presence at thirteen Stations in the North Atlantic, at six in the South 
Atlantic, at sixteen in the South Pacific, and at five in the North Pacific, as well as at one 
or two points in the Indian Ocean. By far the larger proportion of these lie within the 
tropics. The most northerly locality recorded is lat. 41° 15' N. in the North Atlantic; 
the southern limit appears to be about the latitude of Sydney, 34° 13' S. in the Pacific. 
The bottoms range in depth from 7 fathoms to 2675 fathoms. 
Pullenia obliquiloculata has not hitherto been observed in the fossil condition. 
