"must be obtained for that group and
cannot now be to preferred to the
other section of which A. tumida is
the type. This reasoning, according
to my opinion, can only hold good in
case it must be implied that Mr. C.
specially confined the genus to shells
having the precise character of those
in his official list, or pointed out
one of them as a type, or drew up his
diagnosis in such a manner as to
exclude A. tumida.
Mr. C. made the genus in his Syn.
of the Carb. Foss. of Ireland 1844. I
don't say after speaking of the Spiriferæ
2. Endostonicæ, 3. Athyridæ, etc., or
which then is no account of either flamen,
cardinal area, or dorsal hinge. This
distinguishable genus is frequently confounded
with that shell usually named Terebratulæ
in the older works, but is distinguished
by the large spiral appendage behind.