Drawing a sycamore ball

In my opinion, there are few things in nature as difficult to draw as a sycamore seed pod.  I've spent the better part of the morning staring at the thing and finally I think I've figured out how it is constructed; and therefore now I know how I'm going to draw it.  Let me see if I can describe it to you:  What you've got is essentially a sphere within a sphere.  The inner sphere is almost like a soccer ball.  Can you imagine the hexagon patches of a soccer ball all sewn together?  Well in a sycamore ball, each 'patch' is actually a hole in which a seed case grows.  The seed grows and matures in there, and when it has swollen to its finished size, the casing pops open to let the seed out.  What you're left with is the bird-beak-like case poking out of the 'soccer ball patch' inner core.  All together, the open seed cases poke out all around the inner core to create the outer prickly sphere of the sycamore seed pod. 

Here I've started to sketch in inner core, with its irregularly shaped hexagons:

And here is what it looks like as I start to draw in the 'bird beaks':



I know this is a hard thing to draw because I am sighing a lot as I work.  This is dangerous, though, because as I have already mentioned, the material is extremely lightweight and if I sigh too heavily I'll destroy my composition (again.)  Ah well, this is a good exercise in perseverence.  See what good life lessons one can learn from picking up a drawing pencil?  Back to work . . .