Step 10: Lightly sketch the shape of the pteranodon's eyes inside the circle near the top. The shape is similar to a football. When you get the shape right, darken the lines. Add a circle inside for the actual eyeball. Shade the pteranodon's eye except for a tiny circle to represent glare. Add a few lines around the eye for extra detail. Draw a couple of lines above the eye for the bony structure and a few more lines under it for the wrinkly skin.
Step 11: Add a few more curved lines under the eye to represent the body structure of the skull. Draw the nostril as a tiny slit on the left side.
Step 12: Use the initial triangle-like line as a guide to draw the top part of the mouth. Follow the path of the guide but make the shape thinner. The pteranodon's mouth should extend to the inside of the head.
Step 13: Use the triangle-like line at the bottom as a guide to draw the lower part of the mouth. Follow the basic path of the guide as you darken the lines and form the lower jaw. Add a few more lines within the shape of the jaw for the inside of the mouth and the tongue.
Step 14: Use the shape on top of the pteranodon's head as a guide to draw the crest. Follow the guide and darken the lines. Add an extra line near the bottom for the body structure of the eye on the other side.