Further to yesterday’s post about Shylock’s Gaelic and Jewish incarnations, Brendan King has sent me the sources for the tales that he mentions. Knowing that Ink Deskers are sticklers for correct scholarship, I’m posting the sources.
 
Regarding the Irish and Scottish versions, the first was collected by Anglo-Irish playwright J. M. Synge in 1905 and appears in his book The Aran Islands. The second appears in John Francis Campbell’s 19th century anthology Popular Tales of the West Highlands.

The Moroccan version appears in Pinhas Sadeh’s recent anthology of Jewish folktales. According to Sadeh’s commentary, the legend is also very popular among Jews from Iraq and Iran.