Step 10: Lightly sketch the eyes inside the head as two circles. Tarsiers have the largest eye-to-body size ratio of all mammals, so make the eyes big in relation to the head. The eyes should be almost as big as the guide for the muzzle. When you get size of the eyes right, darken the lines. Use the construction lines as guides to help you place the proper distance between the eyes. Tarsiers' eyes cannot move in their sockets. Instead, their heads are able to rotate 180° on their necks.
Step 11: In the middle of each eye, draw a tiny dot for the pupils. If you'd like, you can make the pupils dilated by drawing a circle almost as big as the eyes and shading them in. Off to the side of each pupil, draw a couple of small circles for highlights. You can draw more highlight circles if you'd like. Add some lines round the tarsier's eyes for extra detail. On the inner parts of the eyes, curve the lines down toward the muzzle a bit to create the corners of the eyes. These lines are part of the eyelids, so keep the lines close to the shapes of the eyes.
Step 12: Inside the muzzle guide, below the horizontal construction line, lightly sketch a small circle for the tarsier's nose. When you get the size and position right, darken the lines but make the shape a bit flatter on the sides. Curve the left side inward for the nostril. Inside, at the bottom, draw a tiny line to split the tiny primate's nose.
Step 13: Below the nose, draw a line that's made up of short strokes for the mouth. The left side of the line should stretch outside of the initial circle. Dip the line down in the middle. Darken the lower edge of the initial circle to create the tarsier's chin. Use short strokes as you follow the edge of the circle for a furry texture.
Step 14: Darken the small arc on the top, left side of the head for the first ear. Draw a series of short strokes within the shape for the fur inside the ear. Draw longer lines for the ear's structure. Stretch the lines farther down so that the ear's base is inside the head. Use the arc on the top, right side as a guide to draw the tarsier's other ear the same way. Darken the arc and then draw the strokes inside for the structure and fur.