Slide showing 'Distoma lanceolatum'. Slide shows engraving of individual organism. Label below image reads, 'Fig. 18. - Ciliated embryo of Distoma lanceolatum. After Leuckart.' From the 'Parasites and Their Hosts' series. Small round sticker at upper right corner, '20'. In upper left corner, sticker that reads, 'Laurie, London'. Number '23' written on tape on top edge of slide. Late 19th - early 20th century