>Would love to know which species of turnips those were, for the ones we grow here on the farm would provide only elfin-sized lanterns.

I think that part of the problem is that in Scotland and the North East of England (not so sure about Ireland), turnips are swedes and swedes are turnips, so are bigger and with a flat bottom, more like the size of small pumpkins. I have seen larger turnips around, maybe our wet boggy soil helps them grow bigger!

According to the following site, swedes are also known as swedish turnips and were developed in the seventeen century http://www.vegetables.co.nz/veg/veg.cfm?i=46