The 15th Idyll of Theocritus describes a festival of Adonis in Alexandria in Ptolemaic times. A commenter has suggested that the ancient scholia on Theocritus might contain more information.
I was not aware of the scholia, but a Google search quickly finds a reference to “Scholia in Theocritum vetera by Carl Wendel”. According to the 1911 Encyclopedia Britannica, here, Theocritus actually is extant in papyri of the 2nd century and the 5th, as well as the medieval copies, and there are important scholia in the best manuscripts such as Ambrosianus 222. This all leads me to Eleanor Dickey’s Ancient Greek Scholarship, which is the guide to the scholia.
What does she say about Theocritus (p.63)?:
The old scholia, which fill a volume much thicker than that of Theocritus’ own work, derive from a massive composite commentary assembled from at least two earlier works. One was a scholarly commentary dating to the Augustan period, composed primarily by Theon but also incorporating the work of Asclepiades of Myrlea (first century bc); in addition to many of the scholia, the surviving prolegomena and hypotheses have their bases in this commentary. The second major source of the composite commentary appears to be a work independently composed by Munatius of Tralles in the second century AD and containing a number of gross errors. …
These two commentaries were later combined, along with the work of the second-century commentators Theaetetus and Amarantus; it is likely but not certain that the compilation was done by Theaetetus in the second century. From the fourth to sixth centuries a revival of Theocritan studies resulted in some further alterations to the commentaries, but since no scholars later than the second century are named in the old scholia it is likely that no significant additions were made at that period. The scholia as they have come down to us represent a severely abridged version of the original commentaries, which were used by a number of early scholars in their fuller forms. There is thus a significant indirect tradition for the Theocritus scholia, involving Eustathius, Hesychius, various etymological works, and especially the scholia to Vergil. …
The standard edition of the old scholia is that of Wendel (1914 =TLG), which includes material derived from the indirect tradition and the Technopaegnia scholia but omits the papyri and the Byzantine scholia. The latter can be found in earlier editions of the Theocritus scholia, preferably that of Ahrens (1859), in which they are marked with “Rec”; the papyri must be consulted in their original editions. The definitive discussion of the scholia is also by Wendel (1920, with further references)…
and the references to Wendel are:
Wendel, Carl (1914), Scholia in Theocritum vetera (Leipzig; repr. 1966). Standard edition, excellent. [Google books here]
——— (1920), Überlieferung und Entstehung der Theokrit-Scholien (Berlin; Abhandlungen der königlichen Gesellschaft der Wissenschaften zu Göttingen, philologischhistorische Klasse, NF 17, Nr. 2). Indispensible study of Theocritus scholia, including their origins, the indirect tradition, and the Byzantine scholiasts. [Does not seem to be on Google books]
This is why I like this book. It gives you the orientation you need, and tells you where to find the text. What more could an introduction do? and it should certainly do no less.
The Wendel edition of the Scholia thankfully has an index at the front — so many continental editions of that period make you hunt around –, and the scholia on Idyll 15 are on p.305-317. This material is on the TLG CD, under “Scholia in Theocritum”.
Whether it contains anything of interest to us, tho, my Greek is inadequate to say!