REPORT ON THE FORAMINIFERA. 
427 
The best recent specimens of Bolivina reticulata are from the following localities in 
the South Pacific : — off New Hebrides, 130 fathoms ; off Raine Island, 155 fathoms ; off 
Kandavu, 255 fathoms ; and off Tahiti, 420 fathoms. It occurs also in the South Atlantic, 
mid-ocean, 1425 fathoms. Specimens with intermediate characters, somewhat resemb- 
ling Bolivina decussata, have been met with at Station 144, between the Cape of Good 
Hope and Kerguelen Island, 1570 fathoms. 
Yon Hantken states that the species is not uncommon in both the upper and lower 
Clavidina-szaboi formations of Hungary. 
Bolivina subangularis, H. B. Brady (PI. LIII. figs. 32, 33). 
Bolivina subangularis , Brady, 1881, Quart.. Journ. Micr. Sci., vol. xxi., N. S., p. 59 
Test oblong, tapering, stoutly built, more or less angular, somewhat concave or 
excavated on both sides ; aboral extremity obtusely pointed. The angular contour of 
the transverse section is determined by the prominence of superficial costae, the principa 
of which, six in number, are placed, one down each lateral margin and two down each 
face of the test. Aperture comma-shaped. Length, g^th inch (0'5 mm.) or less. 
A rare variety, nearly allied to Bolivina costata. It occurs at Station 209, Philip- 
pine Islands, 95 fathoms, and at Station 185, off Raine Island, 155 fathoms. 
Sub-family 3. Cassidulininse. 
Cassidulina, d’Orbigny. 
Cassidulina, d’Orbigny [1826], Bronn, Reuss, Egger, Parker and Jones, Williamson, Carpenter 
Brady, M. Sars, Alcock, Winther, Schulze, Hantken, &c 
Burseolina, Seguenza [1880]. 
The arrangement of the test in Cassidulina is in some respects more complex than 
that of any other type of Foraminifera, inasmuch as it combines two distinct modes of 
growth, the biserial and the convoluted. This may be best understood by its analogy, 
in the typical condition, to a broad Textularian or Bolivine shell, doubled or folded 
longitudinally on the median line, and then rolled in the crease so formed from the narrow 
to the broad end. The flaps of each convolution extend nearly or quite to the umbilicus, 
and completely enclose the previous whorls. The aperture is an oblique loop-like 
opening, resembling that of Bulimina. 
If the normal plan of growth be borne in mind, it is easy to understand its modifications, 
as represented in the commoner species, by reference to those of one of the simple 
planospiral types, such as Cristellaria. Thus, both in Cassidulina and Cristellciria 
there are lenticular varieties which have a sharp peripheral edge, oval and compressed 
