From the book, The United States Marines: A History, by BGen E.H. Simmons, NIP, 1976
"There had been "Reservists (Female)" in World War I...
Despite, or perhaps because of this experience, the Marine Corps was the last of the four armed services to organize a Women's Reserve in World War II.
Pressed and prodded on the issue, General Holcomb, with undisguised reluctance, wrote to the Secretary of the Navy....By Holcomb's own frequently recounted story, when he went home that night to the Commandant's House and announced his decision to bring women into the Corps, Archibald Henderson's portrait fell off the wall. President Roosevelt was much more approving..."