Peripheral blood smears from patients with abnormalities of erythrocyte volume homeostasis. (A) A Wright-stained peripheral blood smear (original magnification ×40) from a patient with hereditary hydrocytosis is shown. Numerous stomatocytes, erythrocytes with a central mouthlike or “stoma” appearance, are seen. (B) A Wright-stained peripheral blood smear (original magnification ×40) from a patient with HX showing rare stomatocytes, dessicytes, which are dense, abnormal erythrocyte forms where hemoglobin appears puddled at the periphery, and target cells.