Manufactured by Mego-Motorrad Meixner & Gockerell, Munchen, Elisabethstrasse 29.
The motorcycle which was to be named PAX was for reasons obscure named MEGO, and the story is explained in some detail at cockerell.de.
The name MEGO is derived from the two company owners, Meixner and Gockerell.
Fritz Gockerell entered an agreement with Johann Meixner to build the Pax, under which Meixner had the rights build the motorcycle if it was not completed by May 16th, 1918. Should the motorcycle be manufactured by a third party, the two partners should share the license profits. The name of the machine was changed to Mego-Motorrad (Meixner und Gockerell) and not long after that it became the Megola.
N.B. There was also a British marque, Pax Engineering
Sources: cockerell.de, et al.