FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 397 
face, however, the margin and sometimes the septal furrows are limbate (a feature 
usually wanting in P. Menardii) ; an umbilical knob is sometimes present also ; and 
with this as a nave, and the septa for spokes, the shell has a wheel-like aspect. 
A closely allied and still more conical form (B. Schreibersii, D’Orb., For. Foss. Vien., 
pi. 8. tigs. 4-6), having a stellate umbilicus and neatly radiating septa, is the leading 
member of the group of varieties of P. repanda , among which P. Karsteni is arranged ; 
it is found recent in the muds of the Gulf of Suez and the Red Sea (at 40 fathoms and 
thereabouts), and is fossil in the Tertiary beds of Tuscany and the Vienna Basin. 
Though differing from it a little in details, the North Atlantic specimens here figured 
are still more like Reuss’s figure than is the Arctic specimen, Plate XIV. fig. 15, which 
in some respects is nearer to D’Orbigny’s figure of Pulvinulina Antillarurn (Foram. Cuba, 
pi. 5. figs. 4-6), an allied form. Reuss*s figure is intermediate to the Arctic and North 
Atlantic specimens. 
In Trinity Bay P. Karsteni is rare but large at 133 fathoms, lat. 48°T8', long. 52° 56'. 
It occurs at 2700 fathoms in the South Atlantic. 
Pulvinulina repanda , Fichtel and Moll, sp., Var. elegans , D’Orbigny, sp. Plate XVI. 
figs. 44-46 (North Atlantic). 
Our specimens show an unusually non-limbate condition of Pulvinulina elegans , which 
is a subtype of the P. repanda group, and was chosen as a species by D’Orbigny from 
amongst Soldani’s figures (Sagg. Oritt. pi. 2. fig, 2, R ; Ann. Sc. Nat. vii. p. 276, No. 54). 
P. elegans has a neat, smooth, and highly polished shell, varying always in limbation 
and conicity. The excess of characters in this subtype is found in P. caracolla , Rcemer, 
sp., P. ornata , Roem., sp., and P. D'Orbignii , Rcem., sp. (Norddeutsch. Kreid. pi. 15. 
figs. 22, 24, 25), of the Cretaceous deposits. In our specimens we have nearly an equa- 
lity with P. Partschiana , D’Orb., sp. (For. Fos. Vien. pi. 8. figs. 1-3), excepting as to 
limbation : and, further, we may regard our specimens as feeble forms of P. elegans with 
a tendency towards P. umbonata , Reuss (Zeitsch. d. g. Ges. vol. iii. pi. 5. fig. 35). 
P. elegans abounds at from 100 to 200, and even to 300 fathoms. Forms inter- 
mediate to P. elegans and P. Karsteni are common in clays of the Secondary Forma- 
tions (Oxford and Kimmeridge Clays, and Upper Trias of Chellaston). 
In the North Atlantic P. elegans is common, but small, at 78 fathoms on the eastern 
plateau; rare and small at 1660 fathoms in the abyssal area (“Boreal”); but rather 
common and larger at 1450 fathoms. It is sa 11 at 15 fathoms in the Irish Sea (Brady). 
Genus Spirillina. 
Spirillina vivipara , Ehrenberg. Plate XV. fig. 28 (Arctic). 
For an account of Spirillina ;, see Ann. Nat. Hist. 2 ser. vol. xix. p. 284, and Carpen- 
ter’s Introduct. Foram. p. 180. There is often a difficulty in distinguishing this form 
from its isomorph, the vermiculate Pulvinulina ; the numerous and non -segmented 
whorls decide the doubt in this instance. 
3 H 
MDCCCLXV. 
