Resources for medieval musicology and liturgy
A reproduction of the manuscript 360 of the fonds grec has been published, only the digitalisation of the microfilm in black and white, but in a well readable resolution. Already a look at it reveals, at least in my opinion, that the compilation was made of five parts. If the first part with a collection of anagrammatismoi belonged to the treatise which I doubt, it must be dated even later back to the 15th century or late 14th century. But a simple look at the microfilm reveals, that the hand and style are from different periods, and both parts have nothing more in common that they were bound in one volume which suffered from many bad treatments causing the poor condition of the manuscript.
In conclusion I would dare to date the last part with the treatise to the same date like the one of the Bellermann fragments. I suppose that it originally introduced a Tropologion (following the hypothesis by my dear colleagues Christian Hannick and Gerda Wolfram) which had been written until the 12th century. I see no plausible reason for a later datation.
 XV • Collection of anagrammatismoi (mathemata), ff. 1-8v, obviously not a systematic Menaion taken from a Sticherarion kalophonikon, but some anagrammatismoi of different stichera, an extreme elaboration of one sticheron SAV 570: πλα᾽ ανετειλε το εαρ δευτε ευωχηθωμεν (St. George, 23 April), divide the old sticheron in several parts (interceded by an anagrammatismos about SAV 65 in πλβ᾽). There are other stichera as well.
 XII • Menologion with Akrosticha, ff. 9r-12v, akrosticha about the eirmos ἀνοίξῳ τὸ στόμα μου (echos tetartos) fol. 12
 XII • Collection of grammatic and poetic treatises probably written by an Italian hand, ff. 13r-95v
(b) Another grammar ἀρχὴ σὺν θεῷ τῶν ἀρσενικῶν κανόνων (fol. 20), ἀρχὴ σὺν θεῷ τῶν θηλυκῶν κανόνων (fol. 51v), ἀρχὴ σὺν θεῷ τῶν οὐδετέρων κανόνων (fol. 58r)
(c) Treatise about ῥῆμα ὀριστικὸν ἁπλοῦν πρωτότυπον ζυζυγΐας πρώτης τῶν βαρϋτόνων (fol. 62) whose composition seems close to the Byzantine elementary learning known as "Epimerismi Homerici," but without the quotations taken from the Iliad (titles close to John Anthony Cramer (ed.) Ὁμήρου ἐπιμερισμοὶ, in: Anecdota graeca (Oxford 1835), vol. 1, 147).
See also the similar collection (b & c) in Grottaferrata, Ζ.α. II (cod. crypt. 173), ff. 27-113v
 ΧΙΙΙ • Homiletic manuscript ἀρχὴ σὺν θεῷ τοῦ πρώτου σχέδους (fol. 96-214v)
(a) Katechetic teaching (see also Cambridge University Library, Gg.i.2, fol. 157):
Κύριε Ἰησοῦ Χριστέ ὁ θεὸς ἡμῶν· ὁ ἀσπόρως εὐδοκήσας τεχθῆναι (2) ἐκ τῆς ἁγίας θετόκου καὶ ἀει παρθένου Μαρίας (3) ταῖς πρεσβείαις αὐτῆς· καὶ τοῦ χρυσορρήμονος (4) Ἰωἀννου, φώτισον τὸν νοῦν τοῦ νέου· τοῦ (5) νῦν ἀρξαμένου τοῦ σχεδογραφεῖν· καὶ τὴν καταρ(6)χὴν εὐλόγησον τοῦ σχέδους :—
It follows a homiletic commentary.
(b) Apolytikion, Holy Saturday: Ὀ εὐσχημων ἰωσὴφ ἀπὸ τοῦ ξύλου καθελὼν τὸ ἄχραντόν σου σῶμα (fol. 122v)
(c) Kontakion (13 April): Γεωργηθεὶς ὑπὸ θεῷ ἀνεδείχθης τῆς εὐσεβείας (fol. 131v)
(d) Μεσούσης τῆς ἐορτῆς διφῶσαν μου τὴν ψυχὴν (fol. 137v) etc.
 XII • late copy of Hagiopolites Βιυλίον ἁγιοπολίτης συγκροτημένον ἔκ τίνων μουσικῶν μεθόδων [book of the holy polis ("Jerusalem") constituted by different musical methods] (fol. 216r-237v), presumably an introduction of a Tropologion.