Lebor na hUidre

Lebor na hUidre or the Book of the Dun Cow (MS 23 E 25) is an Irish vellum manuscript dating to the 12th century. It is the oldest extant manuscript in Irish. It is held in the Royal Irish Academy and is badly damaged: only 67 leaves remain and many of the texts are incomplete. It is named after an anachronistic legend that it was made from the hide of a dun cow by Saint Ciarán of Clonmacnoise.
History.
The manuscript is thought to be the work of three scribes, whose handwriting was distinguished by Richard Irvine Best in 1912 and identified with the letters "A", "M" and "H". A and M are believed to be contemporary. A began the manuscript and wrote the opening pages of several of the texts, which were continued by M, who Best identified as Máel Muire mac Céilechair meic Cuinn na mBocht, based on matching the handwriting with two marginal "probationes pennae" or pen tests, in which the scribe wrote his name. A much later note elsewhere in the manuscript names Máel Muire as the person who "wrote and compiled this book from divers[e] books". His murder by Vikings at Clonmacnoise is recorded in the "Annals of the Four Masters" in 1106, giving us a latest possible date and location for the main body of the manuscript. Some time later, "H" (named for his addition of two homilies) added a number of new texts and passages, sometimes over erased portions of the original, sometimes on new leaves. Based on orthography and an English loanword, Gearóid Mac Eoin concludes that H wrote in the late 12th or early 13th century.
After the monastery of Clonmacnoise was broken up, the manuscript came into the possession of the O'Donnell dynasty of Donegal who held it until 1359, when it and the lost "Leabhar Gearr" were used to ransom members of the clan who had been taken prisoner by Cathal Óg Ó Conchobhair Sligigh (d. 3 November 1362). Áed Ruad O'Donnell recovered the manuscript in 1470, and it remained in Donegal at least until 1631, when the compilation of the "Annals of the Four Masters" was completed. Its location is unknown until 1837, when it was part of a collection owned by Messrs. Hodges & Smith of College Green, Dublin, and was cited by George Petrie in an essay on the History and Antiquities of Tara Hill. The Hodges & Smith collection, 227 manuscripts in all, was purchased by the Royal Irish Academy in 1844.
Joseph O'Longan's lithographic facsimile of the manuscript was published by the RIA in 1870. A diplomatic edition by R. I. Best and Osborn Bergin , with the three hands distinguished by different typefaces, was published in 1929. Digital scans of the pages at the Royal Irish Academy have been published on the web by ISOS (Irish Script on Screen).
Contents.
The remaining leaves of the manuscript contain the following texts, in various states of preservation:
Notes on known alternative versions and copies of the tales in the text are given in 