The consensus of western Mongolists to the effect that the written records of Middle Mongolian in the ẖPhags-pa script, along with those in Chinese-character transcriptions, show an "intervocalic hiatus", to be understood as a phonetic zero, in certain forms for which the Uighur - Mongol script employs a velar graph, is reinvestigated on both the pragmatic (orthographic) and the structural (phonological) level, with particular reference to the probable values of the ẖPhags-pa graphs for the laryngeals, studied in the light of the attested values of their Written Tibetan originals. Considerations of the complementary distribution of certain velar initials in Middle Chinese and Old Mandarin are also invoked, to clarify the use of both the Chinese characters and the ẖPhags-pa script in transcribing Middle Mongolian. The investigation points in the direction of understanding these "hiatus" writings not as incorporating or representing a phonetic (or phonological) zero but instead as overt graphic representations of a voiced laryngeal or uvular spirant.