At 08:54 AM 8/20/2004, Andrew Grebneff wrote:
>Both are indeed Gonioceras sp(p).
>Gonioceras is a flattened orthocone... in cross-section the shall has a flattened venter; the dorsum is convex centrally and the edges are tapered to sharp edges, with concave sulci running along either side.
>These beasties have been called "nautiloids", but have incredibly complex siphuncles, unlike the simple siphuncles of true nautiloids.
>I collected Gonioceras in western Newfoundland in 1990.

Thank you for your help!

So in both cases shown on my web page, we have external casts
of the "top" of the nautiloid...   was it a full flattened oval
orthocone?  I haven't found many pictures of Gonioceras on the
web, so it's hard to visualize what the other "bottom" side would
look like.  I think I was misled by the way each chamber's
impression seems to come to a point - but that's because
the cone was rounded and left the bedding plane at that point.

- John

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