Slide showing two diagrams, one of 'Gill filament of Branchiomma' and one 'Dasychone'. Slide shows two black and white diagrams, labelled 'Gill filament of Branchiomma' and 'Dasychone'. Diagrams labelled A & B. Title below image reads 'Fig 182 - A, a gill filament of Branchiomma; B, of Dasychone. a. Axis; f, secondary filaments; o, eye; x, dorsal appendices.' Branchiomma = polychaete worm. Dasychone = another species of annelid worm. Late 19th - early 20th century