12 
of the volutions, and extend to nearly the centre, where they 
are met by numerous obtuse, arcuated ribs, passing over the 
round ambit; aperture semilunar, inclining to a transverse 
ellipsis ; thickness half the diameter of the shell; septa very 
numerous, and beautifully sinuated. Greatest diameter 
upwards of five inches. 
Found in the inferior Oolite, and also at Dundry. 
Named to commemorate that zealous naturalist, the late 
M. Brocchi of Nice, author of the beautiful work, entitled, 
“ Conchiologis Fossil is Subappennina” 
44. A. serratus. — The Serrated Ammonite, pi. VIII. 
fig. 10. 
Ammonites serratus -Sowerby, Min. Conch. I. p. 65, 
pi. 24. 
Discoidal, involute, compressed, carinated, having five volu¬ 
tions two-thirds inserted; with distant, strong arcuated ribs 
extending from the ambit to nearly the middle of the volu¬ 
tions ; numerous curved costee emanate from the inner margin 
of the volutions, and nearly meet the others in the centre ; 
sides of the volutions somewhat concave contiguous to the 
keel, which is nearly cylindrical, ornamented with sharp 
crenillations, and containing the siphuncle ; aperture narrow, 
pentangular, and extending to half the diameter of the shell; 
septa close, with numerous deep undulations. Largest 
diameter four inches, thickness one inch. 
Found in the Marie, parish of Worlingham, near Beccles, 
Suffolk. 
The central volutions of this species are % very thin, and 
specimens are frequently found without them. 
45. A. Sowerbu. —Sowerby’s Ammonite, pi. IX. fig. 1. 
Ammonites Sowerbii .—Miller, MS. Catalogue; Sowerby, 
Min. Conch. III. p. 23, pi. 213, figs. 1, 2, 3. 
Discoidal, carinated; with four volutions, the inner ones 
about half inserted, or, to the base of the tubercles, having a 
series of about nine or ten spiriform tubercles in the centre of 
each, placed upon obtuse ridges; the inner half of the volu¬ 
tion smooth, the outer half with numerous, slightly bending 
ribs, terminating at the keel, which is defined and entire, 
projecting greatly, rounded externally, and almost separated 
from the volutions, with the siphuncle placed in its outer 
extremity; aperture elliptical. 
Found in the inferior Oolite at Deudry. 
There is a variety of this species with a circular aperture, 
and the keel sometimes impressed. In this variety the ridges 
on which the tubercles are seated are more prominent, and 
the carina so far sunk as to have a furrow on each side. The 
inner volutions in this variety are less inflated than in the 
former. 
46. A. Koenigi.—K oenig’s Ammonite, pi. IX. fig. 2. 
Ammonites Koenigi* —Sowerby, Min. Conch. III. p. 113, 
pi. 263, figs. 1, 2, 3. 
Discoidal, convex, with six volutions, the inner ones about 
half inserted ; sides with distant, strong ribs, which assume 
the form of oblong tubercles, commencing at the inner mar¬ 
gins of the volutions, and extending to about the centre, 
where they are met by numerous, slightly arcuated, gently 
raised ribs, which extend over the rounded ambit; aperture 
cordiform, elongated ; septa few, with slightly sinuated lobes. 
Found at Kelloways and Charmoutli. 
In the immature condition this species is more gibbose than 
in the adult, consequently the aperture is nearly orbicular. In 
the perfect shell, the last or body volutions occupies about 
half the diameter of the disk. 
Ammonites* 
This fossil is named in honour of Dr Koenig, of the British 
Museum, an excellent geologist. 
47. A. Listeri. —Lister’s Ammonite, pi. IX. figs. 3 and 6. 
Ammonites Listeri . Martin’s Petrifactions of Derbyshire, 
pi. 35, fig. 3. Sowerby, Min. Conch. V. p. 163, pi. 501, fig. 1. 
Subdiscoidal, thickness nearly equal to its diameter, with 
five or six narrow volutions, the inner ones partly inserted, 
and deeply sunk; back or ambit very convex, broad ; sides 
inversely conical, with numerous, strong sharp ribs, which 
extend over the ambit, and meet on the opposite side, ter¬ 
minating in a series of strong, elevated, pointed tubercles on 
the inner margin of the volutions; general size about an inch 
and a half in diameter, and sometimes reaching two inches. 
Found in the Limestone of Eyem and Middleton, Derby¬ 
shire, in a Shale stratum belonging to the coal formation. It 
occurs in nodules of iron-pyrites or limestone; also in shale 
on the Bradford road, about two and a half miles from Hali¬ 
fax, Yorkshire. This stratum extends to Idle near Calverly, 
and to Parsley in the neighbourhood of Horseforth, and 
stretching in various undulations so far as Leeds. 
This is one of those remarkably thickened species which 
belong to the same tribe as AmmonitesBlagdmi, pi. 12. fig. 9. 
Remote annular depressions are observable upon the inside 
of the casts of this shell, from which it would appear that the 
margin of the aperture was thickened at particular stages of 
its growth. 
48. A. discus —The Quoit Ammonite, pi. IX. fig. 4. 
Ammonites discus —Sowerby, Min. Conch. I. p. 37, pi. 12, 
figs. 1 and 2. 
Discoidal, umbilicate, much compressed, volutions smooth, 
much concealed ; outer margin acuminated; aperture sagit¬ 
tate, occupying half the diameter of the disk, and one-sixth 
in breadth; septa irregularly undulated; aperture sagittate. 
Greatest diameter four inches; thickness half an inch. 
Discovered in a stone quarry near the House of Industry 
at Bedford. 
49. A. Strangewaysi. —Strangeway’s Ammonite, pi. IX. 
figs. 5 and 10. 
Ammonites Strangewasii. — Sowerby, Min. Conch. III. 
p. 99, ph 254, figs. 1 and 3. 
Discoidal, carinated; five volutions, with their sides nearly 
flat; with an obscure concentric furrow, the margin of the 
outer one flattened, slanting from the centre, and the inner 
edges of the others obliquely depressed; the whole crossed 
by numerous slightly raised, twice curved, undulating ribs, 
which are frequently obscure on the inner side and centre of 
the volutions, but larger and more determined on the dorsal 
edge ; each of these ribs forms two semicircles, reversed to 
one another; aperture oblong; occupying nearly one-third 
of the diameter of the disk. Greatest diameter about six 
inches. Discovered at Ilminster. 
50. A. Grkenovu. —Greenough’s Ammonite, pi. IX. figs. 
7, and 8. 
Ammonites Grcmovii, —Sowerby, Min. Conch. II. p. 71, 
pi. 132, figs. 1, 2. 
Discoidal, compressed ; volutions four or five, two-thirds 
inserted, the outer one being nearly half the diameter of the 
shell; with obscure ribs, which are most apparent towards 
the rounded back, over which they pass ; those on the inner 
volutions quite distinct; aperture elliptical, with a deep 
indentation from the insertion of the volution ; siphuncle 
placed near the centre of the back margin of the aperture ; 
septa close, greatly and beautifully sinuated, and locked into 
MOLLUSCA. 
