And just why do these gowns (mostly pitch-black in colour) sport back hoods? Well, the gowns and mortarboards render some uniformity to the graduation ... The Heritage of Dress that, while today ...

University-approved caps, gowns, tassels and hoods must be rented from the "Commencement task ... or 'keepsake' gowns acceptable attire for commencement. Gown Rental Graduation Packages brochure.