"Pilots, Man Your Planes!"   
                                         WWII U.S. Naval Aviation Collector's Guide                                                                              
U.S. Navy A-14 Oxygen Masks

From top to bottom we have the following:

VMF-214 pilots (Magee, Hill & Heier) pose  for the photographer. Although using the new A-14 oxygen masks with improvised elastic or cloth head straps, it would appear that short cord Navy contract microphones were unavailable and longer cord A.A.F. mics were pressed into service.

Napping while awaiting "the call" in the ready room. The oxygen mask tube is secured under the QAS parachute harness.

After their briefing, VMB-433 PBJ pilots await transportation to the flight line. It appears the breathing tube of the center figure, Bill Parks, has been covered with electrical tape for reasons unknown.

When flying at night, 100% oxygen was recommended from take off to landing for better night vision.

VF-11 pilots jot down "the dope". The pilot at left suspends his mask with cotton cord and has had the web snap straps from the mask accessory kit sewn onto his flight helmet.

VF-1 pilots, one of which has secured his mask tube under the chest strap of his "original" backpad kit.

No mask is visible, but we can see the early bright finish Carr snaps installed on this VF-1 pilot's flight helmet.