Disk-Sphere Transformation in Mammalian Red Cells

The purpose of this paper is to try to explain the phenomenon of the transformation of the mammalian erythrocytes from disks to spheres when a small drop of a saline suspension is placed between glass slide and cover-glass. Ponder (1934) several years ago reviewed the work which had been done in connexion with this phenomenon. As was pointed out by Ponder, who was the first to show clearly the necessity of having the glass surfaces in close proximity for the formation of perfect spheres (1928-9), the two explanations which have been put forth to explain the phenomenon are both inadequate. As will be seen later, that of Waller (1930) is somewhat closer to the true explanation than that of Brinkman & van Dam (1920).