(a) The provisions of this subchapter, insofar as they relate to examinations and registrations of optometrists, shall not apply to duly commissioned or appointed optometrists in the service of the United States Government with respect to the performance of any official duties.
(b) The provisions of this subchapter shall not apply to the physicians or surgeons practicing in the Virgin Islands in accordance with the laws of the Virgin Islands, or to any person selling spectacles or eye glasses but who does not assume, directly or indirectly, to adapt them to the eye, nor who neither practices or professes to practice optometry.