Cniiwaity Scliool of ;CLedici?ie OKE PLATE (EIGHT FIGCRES) Ovulatioii in the rabbit \\as first observed and described by Walton and Hammond ( ' 2 3 ) . Snbsec~aeiitly other investigators have repcated these obser~-ations, but, as far as we know, no other descriptions have been pnblished. TVe wished to investigate ovulation further, and to accurate17 record OUT observations by making moving pictures of Ihe actual process. Thc Baldwin-Patten moving picture apparatus ( Patten and IZramcr, '33) was used.