Normal red cells are seen in this field. Mature erythrocytes can be described as round, elastic, non-nucleated, bi-concave discs which appear buff colored on Wright's stained smears. Notice that many of the cells have an area of central pallor which covers about one-third of the cell. The pallor occurs as a result of the disc-shaped cells being spread on the slide. Normal mature red blood cells have an average diameter of 7.2 microns with a range of 6-9 microns. This is approximately the same size as the nucleus of a small lymphocyte, which is often used as a guideline when determining the size of the red cells on a slide.

The average thickness of a normal mature red blood cell is 2.1 microns with a mean corpuscular volume (MCV) of 87 cubic mircons/femtoliters.