I am doing some reference work on the role of the rising decan for judging appearance of the face. Here are three references to this method among medieval texts.

Ibn Ezra

Book of Nativities and Revolutions (trans. Epstein), p. 15. quotes Zahel Ben Basar the Jew (e.g., Sahl) stating 'the ruler of the face [in the sign] indicates the face of the person; and [he] said that he tried it many times. And he is right when the ruler of the face aspects the rising degree.' So far as I have checked, this reference to Sahl is not included in the latest round of translations by Ben Dykes. I am checking out some of the other untranslated material.

Antonius de Montulmo

On the Judgment of Nativities Part 2, PH, p. 28. 'It seems according to Haly that for the most part you ought to judge the form of the native according to the lord of the face of the Ascendant, mixing together the significators of which I have spoken above.' The annotation by Regiomontanus at the beginning of Chapter VIII (p. 22) also mentions the reference to Haly so we know that Regiomontanus knew of this technique.

I downloaded Haly and though I am not a Latin reader, it appears he mentions his decan system in Chapter 1 and applies decans to physiognomy in Chapter 4. If anybody had already or is game to translate the relevant sections, I would be interested in seeing Haly's comments on the rising decan.

Schoener

On the Judgments of Nativities, Book I, trans Rob Hand. Uses Hindu decans to judge whether the native is more like the father or the mother (see p. 88).

Preliminary Conclusion on Transmission of Decans

The uneven treatment of Chaldean decans among authors in the Hellenistic period may reflect their empirical inaccuracy. Neither Ptolemy or Dorotheus used them. If in fact the Hindu decans can be traced to Sahl, that would provide more confirmation of the early Arabic period as a rich melting pot of different traditions, Hellenistic, Persian, Hindu, etc., From Sahl the Hindu decans made their way into the Medieval tradition through a small minority of authors (listed above). Failure of Bonatti's use of them in outlining rules for physiognomy may be one lasting example of Ptolemy's rejection of the decans much earlier.

Any other thoughts, references to the Hindu decans (based on triplicity of signs, e.g., for the sign of Aries, decans are Aries, Leo, Sagittarius, etc.,) in the Medieval literature would be welcomed. Also if anyone wants to take a crack at Haly I would be interested in confirming the source of Montulmo's reference.

RegulusAstrology wrote:If anybody had already or is game to translate the relevant sections, I would be interested in seeing Haly's comments on the rising decan.

Well, I am ready to have a go with a little terse English.
First of all, Ibn Ab? r-Rij?l apparently uses Greek decans: in chapter 3 of the first book he uses simple delineations of the Greek faces similar to the treatment made (as far as I remember) by Hephaestio. This description gives the names of the lords of the faces in the same way as Hellenistic authors. Moreover, among the aphorisms of chapter 5 of the same book he discusses the contrary opinions of various authors regarding confines, faces and other topics, and having spoken of the three systems of faces, the Greek, the Indian, and the one of al-Kind?, he claims "of these the first (i.e. the Greek) is the more rightful, and most of people agree on using it".

The description of the rules of bodily and facial appearance comes from the beginning of chapter 9 of Book 4 which is otherwise heavily dependent on Ptolemy. He says this topic is subtle and difficult to investigate as many testimonies must be collected. He emphasizes the importance of race and parental heritage in dealing with this topic, then he turns to the rules themselves, saying

Ibn Ab? r-Rij?l wrote:If we should want to know the appearance of the native, we must look at the Ascendant, and if we should find its lord there, or its exaltation lord, or the lord of its confine, or the lord of its triplicity, you must judge along the appearance and nature of this planet.
And if you should find many planets on the Ascendant, consider the one being closer to the grade of the Ascendant, or the one having greater power on the Ascendant, and judge along this [planet] for the native. And you must mix with it the lord of the face and the planet to whom the lord of the face gives its virtue.
But if you should find the lords of the dignities of the Ascendant remote from the Ascendant, nor any of them are on the Ascendant, but you should find a peregrine planet on the Ascendant, you must judge the native along the appearance and nature of the planet being on the Ascendant.
But if no planet is on the Ascendant, you must judge the native along the appearance and nature of the lord of the face, especially if it should look upon the Ascendant.
But if the lord of the Ascendant should be cadent from looking upon the Ascendant, so it does not look there, you must see which [of the planets] having a dignity on it (i.e. the Ascendant) looks upon it with a better aspect, and you must judge the native from the nature and appearance of this planet, and you must mix with its color and appearance the color and appearance of the sign where it is, and of its lord, and of the lord of its confine; and you must judge in this way.

Concluding this section, he says that the key for the judgment of outward appearance of the character (if I interpret the slightly obscure expression vis iudicandi formam et faciem ingenii well) must be drawn from the planet while of bodily appearance from the sign where this planet is. He ends with planetary references, saying that Jupiter gives nice shape and limbs, Venus more beauty, the luminaries fair complexion, while the malefics make natives ugly and, as usual, Mercury follows the planet having a contact with it. Moreover, domiciles of benefics make the native nice, the ones of malefics ugly, and fair and dark complexion may be furthered by the time of birth, daytime or night.
In this and the following section (the latter drawn directly from Ptolemy) the question of the facial lord seems not to arise again.

Thanks for the translation. So he uses Greek decans. Interesting that in your last paragraph the comment on the distinction between the ruling planet itself and the sign where the ruling planet resides. I am also seeing many cases where the sign of the ruling planet has a greater impact on facial appearance than the effect of the planet itself. Thanks again.