Surface Absorptive Cells (or enterocytes) - their apical surface has tightly packed microvilli to increase their surface area. This is known as a brush border. The dark line underneath the brush border is the terminal web in which the microvilli are anchored.
Goblet Cells - scattered cells that secrete mucus. The secretion granules are clustered together near the apical surface. This is seen as a clear circular area due to the mucus being extracted during preparation of the specimen.