Just having a trawl through the box and came across a couple that puzzled me.
The one on the right centre is a damaged echioceras - fairly standard stuff - ribs all pointing the same way, easily identifiable keel... The two in the centre, top and bottom, I thought they were the same, but on closer inspection the ribs on these two lean 'forwards', so definitely different. The one on the left has ribs that point backwards. All four have a similar keel and are a similar thickness, so fairly chunky, and not in any way flattened (like a crucilobiceras would be, for example)
Any assistance would be helpful.
I have bought the book that was suggested but, as was said by Andy at the time (I think...) the plates used in the book aren't the best and I'm struggling to match these.
The one thing you will get from breaking rocks with a hammer is a lot of broken rocks...