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CEPHALOPODA Ammonites Fowleri 
J. Buckman, 1844. 
Original description 
(1844. — J. Buckman, in Murchison, Geol. of Chelt., New Ed., pp. 104 and 89). 
[404] « A. Fowleri, Tab. 12. f. 7. — Keel sharp, distinct, volutions 3 to 4, half 
concealed, outer one nearly half the diameter of the whole, ribs many, proceeding in a 
straight direction from the inner margin, and commencing a gradual upward eurve from 
about the middle of the volution, aperture oblong-ovate, shell flat. Diameter, 2 1/2 in. ; 
thickness, a quarter of an inch. 
« Locazrry. — Lias Shales, near the Lansdown Station. Rare. Named after Chas. 
Fowler, Esq., surgeon, of Cheltenham, as a tribute of respect, for his love of the rare and 
beautiful creations of a former world. » 
[89] « Ammonites Fowleri (Buckman). L. S. Vale of Gloucester. » 
OBSERVATIONS 
The description may be thus supplemented : The keel is bordered by concave areas, 
the narrow periphery being concavi-fastigate, and smooth. The volutions are two-thirds 
concealed — the umbilicus is partially obscured by hard matrix, The ribs run up to the 
edge of the periphery with a strong, but gradual forward sweep, and make a slightly waved 
keel on that edge. They may be followed as growth lines across the concave area which 
borders the keel, and shew a continuation of the forward sweep. The whole course of the 
radial line {rib and growth line) in relation to a straight line is shewn marked by white in 
the figure now given. The diameter is practically correct, but the thickness of the aperture 
is certainly half-an-inch. 
In the hard matrix attached to one side of the specimen are two examples of Ammonites 
(Schlotheëmia) lacunatus, J. Buckman. 
Generic position. — Wright figured this species as Arietites denotatus, Simpson, (1878. — 
Monogr. Lias Amm., (Pal. Soc.) PI. vi, fig. 1) and described it as Arietites Collenottit, d'Orbi- 
gny (1881. — Loc. cit., p. 304). He thus placed it in the genus Arielites, sensu lato. Hyatt 
(1889.— Gen. Ariet., Smiths. Contrib., No 673, p. 211) placed this and cognate species in the 
genus Asteroceras. S.S. Buckman (1898. — Quart. Jour. Geol. Soc., Vol. LIV, p.452) removed 
from Asteroceras those species which had a long forward sweep of the ribs (or growth lines) 
on the periphery, and revived for them Waagen’s generic name Arietites, taking Am. Tur- 
neri, Sow., as the type. 4m. Fowleri has this character of the ribs and so it does not belong 
to the genus Asferoceras, which does not possess this feature : it may be placed in Artetites, 
sensu stricto. 
Locality and Horizon. Lansdown Station, Cheltenham, Gloucestershire, Lower Lias (Sine- 
murian), with Schlotheimia lacunata in a hard bed apparently below the horizon of Oxynoto- 
ceras oxynotum. Perhaps it may be more correctly dated as hemera stellaris. For the photographs 
illustrating this species my cordial thanks are due to Mr. J. W. Tutcher, of Bristol, who 
has been at very great trouble in obtaining a good result in this case. 
1904. S. S. Buchman. 
37" 
