REPOET ON THE FORAMINIFERA. 
651 . 
specimens have been obtained as low as 1070 fathoms in the North Atlantic, and 2160 
fathoms in the South Pacific. 
Discorbina bertheloti, var. baconica, Hantken, var. (PI. XC. fig. 1 , a.b.c.). 
Discorbina baconica, Hantken, 1875, Mittheil. Jahrb. d. k. ung. geol. Anstalt, vol. iv. p. 76, 
pi. x. fig. 3, a.b. 
This is an unimportant variety, the test of which is somewhat more stoutly built 
than that of the typical Discorbinci bertheloti, and the margins of the segments on the 
superior side, as well as the periphery of the inferior, are limbate or bordered ; but it is 
not distinguishable from the commoner form by any characters of greater significance. 
Specimens corresponding to the original figures have been obtained from two 
localities in the North Atlantic, depth 600 fathoms and 1180 fathoms respectively. 
Those described by von Hantken were fossils from the upper Clavulina-szaboi 
formation of Hungary. 
Discorbina rarescens, n. sp. (PI. XC. figs. 2, 3; and 4?). 
Test free or adherent, plano-convex ; peripheral edge extended so as to form a well- 
defined keel, often of considerable width ; the five segments of the outermost whorl alone 
visible on the convex face, the last chamber being relatively large, and the sutures even 
and marked only by fine lines ; spiral face somewhat depressed at the umbilicus, the 
valvular lobes of later segments tolerably distinct. Diameter, j^th inch (0’63 mm.). 
Discorbina rarescens is a carinate variety, bearing the same sort of relation to 
Discorbina bertheloti that Truncatulina tenuimargo bears to Truncatulina lobatula. 
It has-been met with off Paine Island, Torres Strait, at a depth of 155 fathoms ; and 
off the Philippines, 95 fathoms. 
Discorbina vesicularis, Lamarck, sp. (PI. LXXXVII. fig. 2, ci.b.c.). 
Discorbites vesicularis, Lamarck, 1804, Ann. du Museum, vol. v. p. 183; vol. viii., pi. lxii. 
fig. 7. 
„ „ Defrance, 1824, Diet. Sci. Nat., vol. xxxii. p. 186; — Atlas Conch., pi. xiv. 
fig. 2. 
„ „ Blainville, 1825, Malacologie, pi. vi. fig. 2. 
Rotalia turbo, var. vesicularis, Parker and Jones, 1860, Ann. and Mag. Nat. Hist., ser. 3, vol. v. 
p. 293, No. 6. 
Discorbma vesicularis, Carpenter, 1862, Introd. Foram., p. 204, pi. xiii. figs. 2, 3. 
„ turbo, var. vesicularis, Parker and Jones, 1865, Phil. Trans., vol. civ. p. 385. 
Some interest attaches to this species from the fact that the segments are separated 
externally by deep fissures ; as well as from the remarkable development of the secondary 
