I k p n r t men f n f Anatomy, rii icersity of Pen71s ylrnii ia, Phi lndelphin THREE FIGURES
During a recent study of linman fetal brain cells in tissue cultures vesicles lined with ependymal cells bearing active cilia were found in cultures from a fetus mhich measured 90 nini crown-rump. Since little is known about these cells in the living state, as most observations have been made 011 fixed and stained material, the following description of these tissue cultures will be helpful in understanding some of the early phases in the derelopnient of the cerebellum.
MATERIAL AND METHOD
The cerebellum of this fetus was in an early stage of derelopment. The hemispheres were oblong plates coiiiiectecl in the mid-line. They were cut into pieces 1 to 2 mm in diameter and used as esplants. The explants were fastened onto the inside walls of test tubes with chicken plasma coagulated with hemostatic globulin. Twelve drops of a nutrient mediuni consisting of Tyrode Locke-Lewis solution, chick embryo extract and hnman placental serum (Hogue, '46) were added to each tube. The tubes weye closed with rubheistoppers and placed in a roller tube apparatus (Gey and Gep, '36) and incubated a t 37ยฐC. d grant from tlir Faculty Research Fund has grcatly aided this research.