Regulations may prescribe all or any of the following, that is to say, a form of certificate for issue to persons whose names are in the register as evidence of their names' being therein, a form of badge for use by such persons and an official title for such use.
If a person—
then, unless he proves that he did not know, and had no reasonable cause to believe, that his name, or, as the case may be, that of the person employed by him, was not in the register at the material time, he shall be guilty of an offence.