Life Drawing Shell Number 3

It's finally here.  The 3/4 marker of the journey that I call, "Shell Drawing Extravaganza".  For this shell, we were required to create a similar, large shell drawing.  For mine, I used contour and cross contour lines to create the shape.  For this third shell, different from the other times, our class used india ink to provide further depth and shape for our shell.  Looking back at this shell drawing, I look forward to making specific changes for our 4th and final shell drawing.  I used a good variety of lines at the point of the shell, but as I moved backwards, I found myself becoming a little worried about how to deal with lines so thin on the larger planes of the shell.  I also look forward to changing up the way I handled the negative space.  When I finished inking the shell I was a little lost as to what I should do with the negative space, so like the impulsive guy I am, I figured that favor fortunes the bold, so I just went to work making drips and splattering the page with ink and water.  It worked in filling the negative space, but I think that my 4th drawing will benefit more from using ink to set up a plane that the shell rests on, because looking at the image above, you'll notice that the shell just sort of sits there in space almost, as if to be floating.  Something I'd also like to do with the 4th shell drawing is the use of space on the page.  I've been struggling with creating a large shell drawing since day one, and while this is the largest shell I've created, I know I can optimize and use an entire page.  I figure if I can create a large enough shell, I can capture details for people even standing 20 feet away from the drawing, which is a success of sorts.