Asterisked clues are normal. In all other clues the wordplay refers to the numbered clue but the definition belongs to one of the clues which intersect it in the grid. In the completed grid, solvers must highlight a 2-word expression which both describes and could account for the theme.

Across                                            1.    Conductor misplacing end of score produces unacceptable sound, getting the bird (12, 3 words) 10.    Core of green space in New York where chicks are at home (5)    11.    Cycle incorporating Early English pedal (6)                    12.    Find out about extraordinary noise made by animal (8)                13.    Elder parent returns with company (5)                        14.    Supplied meat? Lamb's right first time (7)                    15.    Criminal 'ounded with a malevolent intent (7)                    18.    Give new designation to Long Island college (5)                    22.    Guts taken to plunge into river (6)                        23.    Jumble sale is run with haste (6)                        27.    More obscure party backing out of arrangements (5)                28.    Cutback restricts filling of bad tooth (7)                        30.    Advanced after the French cross (7)                        33.    Incense bottled by Pierre Curie (5)                        35.    Gripped by perverted desires, one goes astray (8)                    36.    Eddy's large middle due for massage (6)                        37.    Being the reason one actually ignores the odds? (6)                38.    Fall guy to get rid of murder victim in centre of Basle (12, 4 words)

Down *1.  Very large area covered by standing stone (4)                2.    A game supported by American friends abroad (6)                3.    He's lost when brave women back opponent (6)                    4.    Inner tubes making weird sound (5)                        5.    Rising artist gets gold award (4)                            6.    Fought for honour, receiving fresh head cut (7)                    7.    Handle on first serving dish (6)                            8.    Heading off back in need of assistance (4)                    *9.  Relative is rejected for not fitting on board (7)                    11.  Sort of wave from tense revolutionary leader (7)                16.  Put an end to unhealthy drink (4)                        17.  Born and died under influence of dog star (7)                    19.    I go first, avoiding dead end (4)                            *20.  Prison rising headed by dancer's companion (7)                    21.    Pause as skinflint grabs note (7)                24.    Endlessly,  Rose and Georgia fell out (6)                        25.    Dean's practical knowledge of audience (6)                    26.    Often appear easy-going, but twisted at heart (6)                    29.    An eastern Christian's taken over province (5)                    31.    Quiet address heard without distortion (4)                    32.    Follower expresses doubts about revolutionary leader (4)            *34.    Headless fish found in stream (4)

To enter this competition send your solution in list format (or a grid) indicating the 2 words to be highlighted, to derekharrison@yahoo.com before the 8th August. The winner will receive a copy of the new edition of Chambers Book of Facts, which has been donated by the publishers.
  www.chambersharrap.co.uk