Now without the driver.
Nemo, as Wendax already said, was derived from the factory name:
Nederlandse
Motorrijtuigfabriek.
The Nemo was build in the factory of Jan Jongerius in Utrecht, though the company Nederlandse Motorrijtuigfabriek was started by N.J. Kollewijn & M.L. van Amerongen. In 1950 they had already closed after maybe a dozen were build. I believe this particular example is a 1949 one.