glochidium: a barbed spine or bristle (often tufted on cacti)
spine: a small sharp-pointed tip resembling a spike on a stem or leaf
scopes trial: a highly publicized trial in 1925 when John Thomas Scopes violated a Tennessee state law by teaching evolution in high school; Scopes was prosecuted by William Jennings Bryan and defended by Clarence Darrow; Scopes was convicted but the verdict was later reversed