Detailed Observation with Pencil

This should speak for itself.Using only a 2b pencil and a rubber, I tried to get the form and the tone without it looking too tight. 

The crab claw became very tight as I found it difficult to suggest the smoothness and roundness of the forms. Using hatching made it too angular. Straight lines do not indicate curves. 

The two oyster shells on the stone works better in some ways, not in others. It looks looser but I think that is only because of the looseness of the rock which had straight line. This meant freer strokes with the pencil and the contrast to the fiddliness of the oyster shells.