342 
ME. W. K. PARKER AND PEOPESSOE T. E. JONES ON SOME 
and often of as large a size as those of the North Sea. In the Maestricht Chalk, also, 
K Radicula is present and of moderate size. 
Nodosarici ( Dentalina ) communis , D’Orb. Plate XIII. fig. 10 (Arctic). 
This specimen is a dwarf Dentalina communis * of D’Orbigxy. The obliquity of the 
chambers in this shell begins early, and so does the greater excentricity of the aperture. 
This style of growth is well represented also by D. inornata, D’Orb. For. Foss. Vien. 
pi. 1. fig. 51, and still better by D. Dadenensis, D’Orb. Ibid. pi. 1. figs. 48, 49; both of 
which are well-grown specimens of D. communis. 
Our figured specimen is from mixed shelly sands dredged up at various spots between 
Drontheim and the North Cape by Messrs. MacAndrew and Barrett. It is very small, 
and resembles what is usually found in nearly any muddy sand containing Foraminifera. 
Dentalina communis is an extremely common variety wherever Nodosarian forms occur 
in the clays of the Secondary Formations, but usually it is of small size. It is larger in 
the Gault than in the Jurassic clays ; still larger in the Chalk-marl and Chalk, and in 
the Maestricht Chalk, as well as in the Tertiary beds that yield Nodosarince. It is very 
large in the Crag of Suffolk, and in the Subapennine Tertiaries. Older than the 
Secondary deposits, however, it is found in the Permian limestones of England and 
Germany. 
It is common in the recent state from the Arctic Circle to the Line ; in fact, geogra- 
phically and geologically, it has a very large range. It occurs in many sandy shore- 
deposits; but its favourite habitat is mud at 50-100 fathoms; and is continually met 
with in the deepest soundings, although never abundant there, and generally small. 
Nodosaria ( Dentalina ) consobrina , D’Orbigny. Plate XVI. fig. 3 (North Atlantic). 
Two joints of Dentalina communis , subvar. consobrina , D’Orb. (For. Foss. Vien. pi. 2, 
figs. 1-3) ; the chambers are longish and set on more squarely than in D. communis 
proper ; representing a passage into D. oviculcc, D’Orb. (D. globifera, Batsch). 
This is small and rare at 1776 fathoms in the North Atlantic, lat. 52° 33', long. 21° 16'. 
Nodosaria ( Dentalina ) pauper at a, D'Orbigny. Plate XIII. figs. 8, 9 (Arctic). 
We have here a very common subvariety of Dentalina communis , in which the pri- 
mordial chamber is relatively large, the septa but slightly oblique, and the aperture 
almost central ; the shell is smooth, nearly cylindrical, and not constricted at the septa 
in the earlier portion of the shell (as shown in our figures 8 and 9) ; as the animal 
advances in growth, the chambers take on a more vesicular shape. D. pauperata, D’Orb. 
For. Foss. Vien. pi. 1. figs. 57, 58, is the same as our figured specimens; and D. 
brevis, D’Orb. Ibid. pi. 2. figs. 9 and 10, and many other named forms, are scarcely dis- 
tinguishable. 
* Annales des Sc. Nat. vol. vii. p. 254, No. 35 ; Mem. Soc. Geol. Prance, iv. p. 13, pi. 1. fig. 4. 
