Note 21 — PROLEGOMENA.

A complete ovum, with the investing cortical membrane, and the entire decidua expelled nine weeks and three days after the last regular menstruation, in the case of a lady recently married, whom I attended (March, 1833), has afforded me ample opportunity of verifying the above and most of the previous propositions, through a careful dissection of the parts under water, and the use of the microscope.