To test the numerous and contradictory statements regarding the presence of smooth muscle in the wall of the Graafian follicle, the author examined ovaries from the cow, pig, rabbit, guinea pig, and rat. Susa-fixed paraffin sections were stained by hematoxylin-van Gieson, azan, hematoxylin-eosin, and Fe hematoxylin, with the usual contradictory results. Although K is abundant in muscle, histochemical tests for that element were found unreliable. For examination by the polarizing microscope, ovaries of the cow, pig, rabbit, and guinea pig were fixed in abs. alc., passed through methylbenzoate-celloidin, and imbedded in paraffin. The retardation on imbibition of fluids of various refractive indices (methyl alcohol, acetone, ethyl alcohol, xylene, and others) was measured for the Graafian follicle wall and, as a comparison, for the muscle of the tunica media of an adjacent artery. The differences in retardation proved that there was no musculature in the thecal wall.