There's a photograph, c.1868, of a Kerry spailpin (spalpeen) in a wee book called "People and the Land" by Dr. Jonathan Bell (of the Ulster Folk and Transport Museum), Friar's Bush Press. (it's probably a well known photo from some other source).                                                            

Bell writes "spailpin means 'a short spell' and these workers were generally hired for jobs which lasted only a few weeks. Most spalpeens came from Cork, Commemara and Kerry. Some went to England to work but many also travelled within Ireland particularly to counties Limerick, Waterford, east Galway, and parts of Leinster. In the later 19th century spalpeens were most commonly employed as potato diggers". Anybody wanting the a copy of the photo just send me their email address.