REPOET ON THE FORAMINIFERA. 
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same set of forms. Schwager, however, takes what appears to be a much more reasonable 
view of the features in question, and in his admirable memoir on fossil Foraminifera from 
the Nicobar Islands, has assigned one of these compressed and carinate forms to the 
genus Bigenerina , thereby asserting their affinity with the cylindrical varieties having 
the same typical structure. It is true that the aperture of Bigenerina capreolus 
and Bigenerina pennatula, adapting itself to the shape of the terminal segment, is 
generally fissurine ; but this character, which only applies to the later portion of the 
test, is by no means invariable, and examples are not wanting in which the orifice is of 
oval form, and differs but little from that of occasional specimens of the cylindrical 
species. 
In the recent condition, Bigenerina capreolus is best known as a North Atlantic type. 
It is found in some of the “ Porcupine ” dredgings, but I have not been able to trace it 
further north than about lat. 50° N. It is common off the Azores, 450 fathoms ; off the 
Canaries, 600 fathoms ; and off the Danish West Indies, 390 to 450 fathoms. In the 
South Atlantic it has been taken at two Stations, off the coast of South America, near 
Pernambuco, depth 350 and 675 fathoms respectively. The specimens originally 
described by d’Orbigny were obtained from the Adriatic. 
Owing to the confusion of names, there is some uncertainty in the record of the 
occurrence of the species in the fossil condition, and it is difficult to state its geological 
distribution with any degree of accuracy. It is known, however, to occur as far hack as 
the Eocene formation of the Bavarian Alps (Giimbel), and the Clavulina-szaboi beds of 
Hungary (Hantken) ; and there is little doubt of its presence in company with Bigenerina 
pennatula in the later Tertiaries of Italy. 
Bigenerina pennatula, Batsch, sp. (PI. XLV. figs. 5-8). 
“ Orthoceratia Pupa," Soldani, 1791, Testaceographia, vol. i. pt. 2, p. 99, pi. cviii. fig. D.E.F. 
Nautilus ( Orthoceras ) pennatula, Batsch, 1791, Conchy 1. des Seesandes, No. 13, pi. iv. fig. 13, 
a.-d. 
Vulvulina elegans, d’Orbigny, 1826, Ann. Sci. Nat., vol. vii. p. 264, No. 3. 
Lingulina soldanii, Id. Ibid. p. 257, No. 3. 
Textularia corrugata, Costa, 1857, Mem. Acad. Sci. Napoli, vol ii. p. 125, pi. i. fig. 15. 
Bigenerina nicobarensis, Schwager, 1866, Novara-Exped., geol. Theil, vol. ii. p. 196, pi. iv. fig. 
7, a.-c. 
Venrnna nummidina, Giimbel, 1868, Abh. d. k. bayer. Akad. Wiss., II. Cl., vol. x. p. 648, pi. ii. 
fig. 84, a. b. 
Grammostomum elegans, Parker, Jones, and Brady, 1871, Ann. and Mag. Nat. Hist.,ser. 4, vol. 
viii. p. 170, p. xi. figs. 121, 123. 
Bigenerina pennatula is very closely related to the species last described, but differs 
from it in the obtuse rounded outline of the aboral end of the test, the relatively smallei 
number of Textularian segments, and the increased development of the linear series. 
(ZOOL. CHALL. EXP. PART XXII. 1883.) Y 48 
