17 
will indicate its rescinblanco to Ti'emanotm rather than to Bucfnihi. In all 
three the volutions are in the same plane, there is an unihilicns on hotli sides, 
and a much expanded trumpet-shaped aperture ; hut in Biicanla the hack of 
the body whorl is simply carinate, whereas both in Tremanotm and the 
llaAvkeshiiry shell the carina hears traces of a series of oval apertures exteudim^ 
along its course — a very important structural difference. An inspection of 
the accompanying sketches Avill at once illustrate these distinctive features. 
The opinion has heen advanced by Mr. S. A. Miller^ that the “ supposed 
openings on the cast represent the sjnnes upon the hack of the anterior part 
of the last whorl of the shell, and the fossil is a true BncAniia.'’’ 
“ On the other hand, tiie late Mr. E. ]h Meek, in an able article, 
‘ Note on the affinities of the Bellerophontidm,’f used the row of isolated oval 
0})cnings in Ti'cmanotm as an argument for placing the family amongst the 
Erosohranchiate Gasteropoda. lie says : ‘ Now, as wo have no examples, so 
far as known to the writer, cither amongst the Iletoropoda or Cephalopoda, 
living or extinct, of a shell with isolated siphonal openings, while Ave have 
many such examples amongst the Prosohranchiate Gastero]Aoda — such, for 
instance, as in the Ilaliotidoc, Eissurellidu}, and Pleurotomariidro — the hearing 
tliis feature in the newly discovered type has on the question respecting the 
affinities of the Bellerophontidaj Avill he readily understood. In other Avords, 
it indicates for the family a position near the Eissurellidnc and Haliotidse, and 
hetAveen those groups and the Pleurotoniariidm.’ Again he adds : ‘ It Avill 
he seen that the shell under consideration (l.e., TrememotnsJ presents exactly 
the form of Bucania, from Avhich it only differs in the peculiar and interest- 
ing character of haAnng along the middle of the dorsal side a roAv of isolated 
OA'al siphonal openings.’ 
“It is manifest from these remarks that Mr. Meek did not for a 
moment regard the marking’s on Professor Ilall’s TremanotuR as ‘ casts 
representing the spines on the hack of the outer part of the last Avhorl,’ as 
suggested by Miller, hut ratlier as genuine siphonal openings. If any further 
proof is Avanting, it can he obtained by an inspection of the beautiful figures 
of Tremanotiis lon(jUuduudls, from the Wenlock beds of Gotland, giA’cn by 
Dr. G. Lindstrom,! in Avhicli the shelly matter of tlie mollusc has been 
retained, and the siphonal openings preserved in great ])erfection. Even a little; 
more attention oir Mr. ]\Iiller’s ])art to American palaeontological literature 
* Cat. American I’al. Foss., ‘2iul Edit., 18S5, p. .804. 
t I’roc. Acad. Sci., Chicago, 188(5, 1, p. Jl. 
* Kongl. Svenska A’ct.-Akad, Handlingar, 1884. lid. xix heft. 2, No. (i, p. 8G. t. 4, f. 1-7. 
11a 124—88 E 
