gomphoceras ellipticum

[DE&i]

I'm quite sure this is gomphoceras ellipticum would anyone know what the the thin black spine's are that appear to be adhered to the fossil. 

[TqB]

I get the impression they're sections of thin shell rather than spines. Maybe broken septum.

[DE&i]

That's interesting @TqB I was going to use this photo as an example. Think perhaps the line's indicated by the letter "s" might mean something.

[TqB]

I'm not certain but I think the Vs might represent growth lines on the external shell. These show the earlier stages of the hyponomic sinus which becomes such a marked feature of the adult living chamber, as shown at the top.

 

By the way, Gomphoceras is a dodgy generic name. According to the Treatise (Mollusca part K), it's a genus dubium , unrecognizable "until dorsal element of peristome [aperture edge] and internal features are known". (Admittedly that's 1964 and the revision is still in preparation - it doesn't look as if anyone else has done it yet either.)

Puzzling as the aperture is complete in the drawing - maybe it's not the same species as Sowerby's original type. Taxonomy gets like that all too often...