Science Interlude : Snapping Turtle Skull

The following are simply photographs from a recent exercise in observing a Snapping Turtle skull.

Using a proscope, (essentially a hand held microscope but with less intense magnification) closer observations were made. Note the multiple textures exhibited by this single bone.

Somewhat porous looking spongy bone. Note the microfracture that almost bisects the image.
This was probably an active seam of the bone during the animal's life, allowing the skull to move and change shape through growth and maturation.

Edge of Optic or Nasal cavity, where keratinaceous beak grows. 

The difference between the spongy bone (filled with holes for blood vessels and tissue)
and the sheet-like keratin beak, implies that the bone is living matter, while the beak is hard, protective and dead. 
(it is the same material as finger nails, hair, and rhino horn, after all.)

A view through the eye (at other orifices).

Beak surface

A different type of bone - the long protrusion at the back of the skull featured an unusually smooth texture. In humans this kind of texture is found on the sternum (chestplate) or scapula (shoulder blade), both clear examples of a flat surface on which sheets of muscle are overlaid. It is rather unusual to see something like that on a skull. Perhaps the large neck muscles that power the animal's head or connect it to it's shell are located at this site?