The Academic Costume Code
As usually followed by American colleges and universities, but following the specifications listed below.
In all cases the material must be the same as that of the gown.
Black, in all cases.
The length of the hood worn for the bachelor's degree must be three feet, for the master's degree three and one-half feet, and for the doctor's degree, four feet. The hood worn for the doctor's degree only shall have panels at the sides.
The hoods are to be lined with the official color or colors of the college or university conferring the degree; more than one color is shown by division of the field color in a variety of ways, chevron or chevrons, equal division, etc. The various academic costume companies maintain complete files on the approved colors for various institutions.
The binding or edging of the hood is to be velvet or velveteen, two inches, three inches, and five inches wide for the bachelor's, master's, and doctor's degrees, respectively; the color should be indicative of the subject to which the degree pertains (see above). For example, the trimming for the degree of Master of Science in Agriculture should be maize, representing agriculture, rather than golden yellow, representing science. No academic hood should ever have its border divided to represent more than a single degree.
In the case of the Doctor of Philosophy (Ph.D.) degree, the dark blue color is used to represent the mastery of the discipline of learning and scholarship in any field that is attested to by the awarding of this degree and is not intended to represent the field of philosophy.