EOEAMINIEERA FKOM THE NORTH ATLANTIC AND AECTIC OCEANS. 371 
Textularia agglutinans , Yar. ( Bigenerino ) Nodosaria, D’Orb. Plate XV. fig. 25 (Arctic); 
Plate XVII. figs. 80 a, 80 b (North Atlantic). 
Bigenerince are Textularice that commence with alternate biserial chambers and com- 
plete themselves with a uniserial set, the aperture becoming terminal, central, round, 
and sometimes pouting. 
JBigenerina Nodosaria , D’Orb. (Ann. Sc. Nat. vol. vii. p. 261, pi. 11. figs. 9-12; and 
Modele, No. 57), is usually sandy, and commences with flat interlacing of chambers, as 
in T. agglutinans, D’Orb. ; whilst B. digitata, D’Orb. (Modele, No. 58), begins with a 
conical set of chambers, as in T. gibbosa, D’Orb. 
At the Hunde Islands (Dr. Sutherland) B. Nodosaria is extremely small, but common, 
at 60 to 70 fathoms. 
On the marginal plateau off Ireland it is common at 78 and 90 fathoms, coarsely 
arenaceous and of fair size. 
B. Nodosaria lives in the Mediterranean and other seas, being widely distributed ; it 
keeps a good size, and prefers muddy bottoms, flourishing down to 200 or 300 fathoms. 
Textularia agglutinans , -Var. [Bigenerino) digitata, D’Orbigny. Plate XVII. fig. 81 
(North Atlantic). 
B. digitata, D’Orb. (Modele, No. 58), may be said to be a smooth, rusty subvariety 
of B. Nodosaria, with a conical instead of flattened apex. 
On the marginal plateau of the North Atlantic B. digitata is rare and small at 78 
fathoms ; the figured specimen is obscure, and may be regarded as feebly developed. 
B. digitata occurs in company with B. Nodosaria in the Mediterranean and elsewhere. 
Textularia agglutinans, D’Orb., Var. ( Verneuilina ) polystropha, Iteuss, sp. Plate XV. 
fig. 26 (Arctic). 
When Textularice have a triple row of alternating chambers, as is not unusual with 
them, they are termed Verneuilince ; having commenced triserially, they may afterwards 
take on a biserial or uniserial arrangement of chambers, and are known as Gaudryince, 
Clavulince, &c. Some that have a triple series of chambers are so much twisted on the 
axis as to have a Buliminoid aspect ; a slight approach to this condition is shown in 
Verneuilina polystropha ( Bulimina p o ly stropha , Reuss, Bohm. Kreid. vol. ii. p.109, pi. 24. 
fig. 53 ; Polymorphina silicea, Schultze ; Bulimina arenacea, Williamson). In Verneuilince 
the aperture ceases to be transverse, becoming drawn upwards, as it were, across the 
septal plane more and more in the later chambers, until it ceases to be even a notch, 
and becomes terminal and round, as it is in Bigenerince. 
V. poly stropha may be said to be a small, vesicular, arrested Verneuiline Textularia-, 
sandy, twisted on its axis, and very red in colour. It is of wide distribution, living in 
all latitudes ; and is found fossil in the Tertiary and Cretaceous beds. 
It is often of much larger size than our figured specimen, which is from the Hnnde 
Islands (Dr. Sutherland); where V. poly stropha is common and small at 25-40 fathoms, 
and very common and small at 60-70 fathoms. 
