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THE VOYAGE OF H.M.S. CHALLENGER. 
less inflated and the sntures excavated. It is allied on one hand to Nodosaria communis, 
and on the other to Nodosaria mucronata ; from the former it differs in its stouter 
proportions and flush sutures, and from the latter in its less rapidly tapering contour and 
rounded initial end. 
The variety is not common in the living condition, and it is difficult to lay down its 
area of distribution, distinct from that of Nodosaria communis. It has been observed 
chiefly in the North Atlantic, at depths of less than 400 fathoms. 
As a fossil it has been obtained from the Gault of Germany ( Dentalina nana, Eeuss) ; 
from the Septaria-clays of Germany (Eeuss, Schlicht) ; and from the Miocene of Transyl- 
vania (Neugeboren). 
Nodosaria ( D .) mucronata , Neugeboren (PI. LXII. figs. 27-29 ; monstrous specimens, 
figs. 30, 31). 
“ Ortboceras intortum ,” Soldani, 1791, Testaceographia, vol. i. pt. 2, p. 98, pi cv. fig. V. 
Nodosaria ( Dentalina ) obliqua, d’Orbigny, 1826, Ann. Sci. Nat., vol. vii. p. 254, No. 36, 
Modtle, No. 5. 
Dentalina mucronata, Neugeboren, 1856, Denkschr. d. k. Akad. Wiss, Wien, vol. xii. p. 83. 
pi. iii. figs. 8-11. 
,, plebeia, Terquem, 1870, Foram. du Syst. Oolith., 3 i6me mem. , p. 267, pi. xxix. 
figs. 3-11. 
„ p. 268, pi. xxix. iff. 13-17. 
„ bicorms, J 11 ° 
Nodosaria mucronata, Reuss, 1870, Sitzungsb. d. k. Ak. Wiss. Wien, vol. lxii. p. 475, No. 30; — 
Scblicbt, 1870, Foram. Pietzpubl, pi. xxxviii. fig. 6, &c. 
Dentalina communis, subvar. obliqua, Parker, Jones, and Brady, 1871, Ann. and Mag. Nat. Hist., 
ser. 4, vol. viii. p. 264, pi. ix. fig. 47. 
,, obliqua, Wright, 1880, Proc. Belfast Nat. Field Club, 1879-80, App., p. 207. 
The Nodosaria ( Dentalina ) obliqua of the “ Tableau Methodique ” is exemplified by 
a tapering shell, somewhat broad near the oral end, and with oblique sutures which are 
marked externally by slightly excavated lines. It is a tolerably well defined sub-varietal 
form, but the name applied to it had previously been assigned by Linne to a costate 
variety of the same genus. 
Dentcdina mucronata, as figured by Neugeboren, presents almost identical characters, 
but the primordial end of the test is more definitely pointed. In deep-water specimens 
the shell-wall is often very thin and the septation defective, and monstrous developments, 
such as are shown in figs. 30, 31, are not unfrequent. As stated by Eeuss in his notes 
upon von Schlicht’s figures ( loc . cit.), Nodosaria mucronata is one of the transition forms 
connecting the genus with Marginulina, and is closely allied to Marginulina apiculata 
of the Chalk (Haiclinger’s Naturw. Abhandl., vol. iv. p. 28, pi. ii. fig. 18). 
Nodosaria mucronata has been collected in comparatively shallow water on our own 
