Contents

1 Editorial

2 John Wint John Wint: President of the YNU, 2010 - 2011

3 G.T.D. Wilmore 2010 Presidential Address: Alien Plants – An Ecological Perspective

15 Anthony Wardhaugh Pellets: Coughing Up The Truth Or Flight Of Fancy?

18 Michelle Farrell and Jane Bunting The Crackles Bequest Project

19 R. GoulderTurnover of freshwater-plant taxa: the example of an ornamental lake in East Yorkshire

28 Joseph P. Botting Community development among Hemiptera and other insects on a brownfield site in south Leeds*

35 W.A. Ely The state of the Union's ichneumon records

39 Michael E. Archer The Aculeate Hymenoptera (wasps, ants and bees) of the Lindrick area in Watsonian Yorkshire*

45 Adrian Norris and David Lindley The Slender Slug Malacolimax tenellus in Yorkshire

46 Anthony Lane The Particoloured Bat Vespertilio murinus found in the East Riding of Yorkshire (VC61)

47 Anthony Lane First records of Leisler's Bat Nyctalus leisleri in the East Riding of Yorkshire (VC61)

49 Tom Higginbottom A joint meeting to Melton Wood

51 Book Review Seeds, Sex & Civilisation by Peter Thompson

52 Book Review People, Places and Species – a History of the Study of Wasps, Ants and Bees in Watsonian Yorkshire by Michael Archer

53 Albert Henderson and Adrian Norris Yorkshire Naturalists’ Union Excursions in 2010

71 YNU Excursion Circulars 2011

79 Calendar of Events