694 
THE VOYAGE OF H.M.S. CHALLENGER. 
Atlantic, 1025 to 2350 fathoms; one in the Southern Ocean, 1570 fathoms ; seven in the 
South Pacific, 610 to 1940 fathoms ; and four in the North Pacific, 500 to 2900 fathoms. 
These are scattered over an area stretching from lat. 60° N. in the North Atlantic, to lat. 
46° S. in the Southern Ocean. 
Pulvinulina crassa, d’Orbigny, sp. (PL CIII. figs. 11, 12). 
Rotalina crassa, d’Orbigny, 1840, Mem. Soc. geol. France, vol. iv. p. 32, pi. iii. figs. 7, 8. 
Pulvinulina crassa, Owen, 1867, Journ. Linn. Soc. Lond., vol. ix., Zool., p. 148, pi. v. figs. 8 (?), 9. 
„ „ Brady, 1879, Quart. Journ. Micr. Sci., vol. xix., N. S., p. 80. 
The morphological features of Pulvinulina crassa are intermediate between those of 
Pulvinulina canariensis and Pulvinulina michelinictna. The superior face of the test is 
nearly flat, the inf erior highly convex and slightly excavated at the umbilicus; the seg- 
ments are somewhat inflated, and the contour altogether less angular than in the latter 
species ; the surface of the shell is often rugose on the inferior side. In the peripheral 
outline and segmentation of the superior face it resembles Pulvinulina canariensis, 
whilst the convexity of the inferior side approaches that of Pulvinulina micheliniana. 
It may be regarded as the isomorph of Truncatulina lobatula. 
Surface-specimens of Pulvinulina crassa have been identified at one Challenger 
Station in the South Atlantic, and at eight in the South Pacific. 
Its area of distribution, as determined from bottom-specimens, is scarcely so wide as 
that of either of its immediate allies, nevertheless it has been collected at ten Challenger 
and “Porcupine” Stations in the North Atlantic, depths 725 to 2740 fathoms, the most 
northerly being at lat. 54° 53' N. ; at seven in the South Atlantic, 420 to 2350 fathoms; 
at one in the North Pacific, 2250 fathoms; at fifteen in the South Pacific, 150 to 2335 
fathoms; and at two in the Southern Ocean, 1375 and 1950 fathoms respectively, the 
most southerly being at lat. 53° 55' S. 
The fossil remains of the species are not uncommon in the Chalk of the neighbour- 
hood of Paris and of some parts of Kent, but I find no mention of their occurrence in 
later formations. 
Pulvinulina micheliniana, d’Orbigny, sp. (PL CIY. figs. 1, 2). 
Rotalina truncatulinoidcs, d’Orbigny, 1839, Foram. Canaries, p. 132, pi. ii. figs. 25-27. 
,, micheliniana, Id. 1840, Mem. Soc. geol. France, vol. iv. p. 31, pi. iii. 
figs. 1-3. 
Discorbina micheliniana, Reuss, 1865, Sitzungsb. d. k. Ale. Wiss. Wien, vol. Iii. p. 455, No. 1. 
Pulvinulina repanda, var. menardii, subvar. micheliniana, Parker and Jones, 1865, Phil. Trans., 
vol. civ. p. 396, pi. xiv. fig. 16 ; pi. xvi. figs. 41-43. 
,, micheliniana, Owen, 1867, Journ. Linn. Soc. Lond., vol. ix., Zool., p. 148, pi. v. 
fig. 17. 
„ ,, Brady, 1879, Quart. Journ. Micr. Sci., vol. xix., N. S., p. 80. 
