Content

161 R. Goulder Freshwater plants and SSSI canals in the East Midlands and North of England 4: an overview

176 Kenneth J. Phipps An ichthyosaur vertebra from the Cave Rock Member of the Kellaways Formation at South Cave Station Quarry, Yorkshire

178 Richard Shillaker and Martin Roberts Mass mortality of adult Common Toads at two breeding sites in Yorkshire*

191 Michael Pearson A survey of the flowering plants found on drystone walls in the Yorkshire Dales

196 Colin A. Howes Yorkshire Naturalists at War: Part 2 - on the Home Front

203 P.Hinks Field Note: Red-veined Darter in a Flash

204 Terry Crawford & Adrian Norris YNU Conchological Section Report for 2017

205 T.L. Blockeel YNU Bryological Section Report for 2016

211 Ken Gartside The hoverfly Callicera rufa - The first Yorkshire record (including methodology for artificial rot-holes)

214 Yorkshire Naturalists’ Union Conference 2018

215 Andy Millard Ellen and her frogs

221 Yorkshire Naturalists’ Union Excursions in 2017

239 Erratum & RetractionThe Naturalist 1094: 47; The Naturalist 1091: 58-60

240 Calendar

218 Book ReviewBritain’s Spiders. A field guide by L.Bee, G.Oxford & H.Smith