“They call me the Queen of Snails,” Lyn Paxman says with a laugh as she guides me through her Somerset farm’s snail pens. As she talks about her free-range molluscs, she readies tiny electric fences and lays down salt traps for the approaching summer snail-herding season. Last year, Paxman’s prized Helix Aspersa Müller (the common garden snail) escaped and made short work of her vegetable patch. This year, she’s fortifying the farm. Eating snails fell out of fashion long ago in England, but in Somerset, Paxman and her partner, Rob,…