PLATE XXVI. 
1, 2. Nummulites Comptoni. ( Compton's Nummulite.) Lenticular, obtusely carinated; surface smooth, 
with about ten, well-marked septa; aperture acutely triangular, formed of two, arcuated lips. Diameter 
not X V in. 
3,4,5. N. Variolaria. (Variable Nummulite.) Very convex, smooth; with four or five volutions; margin 
obtuse ; septa about twenty, forming rays near margin. 
6,7,8. N. Laevigata. (Smooth Nummulite.) Lenticular, smooth ; with about twelve, compressed volutions; 
sides convex, plain, except having a few elevated dots and slightly undulated in centre; margin narrow, rather 
obtuse, finely striated; aperture narrow. 
9, 10, 11. N. Elegans. (Elegant Nummulite.) Compressed, smooth; with about six volutions; septa 
numerous, gently curved from axis ; aperture prominent. 
12, 22. Bellerophon Tangentialis. (Tangent-Ridged Bellerophon.) Cylindrico-globose; umbilicus largely 
rounded ; aperture expanded; ambit broad, with acute, narrow carina, whence straight ridges and sulci, 
perpendicular to keel, forming tangents to inner margin. 
13, 15. B. Urii. ( Lire’s Bellerophon.) Globular; sides of aperiure expanded; axis solid ; shell smooth, with 
many, regular, spiral, shallow sulci, and rounded, narrow ridges ; without keel. 
14, 20. B. Woodwardii. ( Woodward’s Bellerophon.) Discoidal, lenticular, sub-rhomboidal, with four or five 
volutions; sides angular, with many, concentric series of granulated lines; back rounded, with linear sulcus in 
centre; aperture obovate, with angulated sides. 
16, 30. B. Tenufascia. (Thin-Banded Bellerophon.) Globular; aperture expanded; mesial keel thin, 
elevated, acute, with fine, close, transverse stria); umbilicus small. Greatest diameter, 3 in. 
17, 19. B. Hiulcus. (Gaping Bellerophon.) Globose ; expanding widely from central volutions; mesial 
keel, broad, flat; axis perforated ; sides with close-set, elevated striae from axis and passing obliquely to keel; 
front sinus deep, producing arcuated striae upon carina, whose sides are well defined by sharp, depressed lines ; 
aperture expanding. 
18, B. Spiralis. (Spirally-fur rowed Bellerophon.) Ovate, umbilicate; back and edges of umbilicus obtusely 
angled, with many spiral ridges and sulci ; whole surface minutely granular; lip of aperture somewhat trian¬ 
gularly pointed behind. 
21. B. Decussatus. (Decussated Bellerophon.) Sub-globose, or longitudinally ovate, with small, spiral 
ridges and sulci, crossed by finer, thread-like, arcuated lines, producing decussated appearance ; aperture much 
expanded; axis solid; mesial keel tumid, rounded, covered by the striae. 
23, 26. B. Sulcatus. (Furrowed Bellerophon.) Discoidal, with large, shallow umbilicus ; sides inflated and 
crossed by many narrow, curved sulci; mesial keel elevated, with arcuated sulci ; aperture expanded, arcuated, 
elevated behind. 
24, B. Costatus. (Ribbed Bellerophon.) Sub-globose, with small, rounded umbilicus; mesial keel broad, 
depressed; striae sharp, emanating from umbilicus in arcuated form, ending in a deep, V-shaped, dorsal sinus; 
aperture large, expanding. 
25, 27. B. Apertus. (Open Bellerophon.) Nearly spherical; inner volutions concealed; axis solid, very 
thick ; sides smooth ; sides of aperture expanded; extremities squarish ; without mesial keel; back rounded. 
28. B. Ovatus. ( Oval Bellerophon.) Ovate, gibbose, with shallow, central umbilicus ; inner volutions con¬ 
cealed ; sides rounded; surface smooth; aperture obtusely sagittate, with sides narrow. Greatest diameter 
thrice thickness of shell. 
29. B. Expansus. (Expanded Bellerophon.) Sub-discoidal; umbilicus concealed ; sides greatly produced, 
crossed by wide-set sulci; mesial keel elevated in arcuated form ; aperture wide, gaping. 
31, 32, 33. B. Cornu-Arietus. (Ram’s-Horn Bellerophon.) Very thick, smooth, compressed ; volutions few, 
inner ones minute ; near aperture on back with longitudinal, carinated, regular, dorsal sinus, dividing aperture 
into two lobes; aperture large, dilated ; axis solid, very thick. 
( 30 ) 
