Slide showing tinted diagram of 'Cross-section through larva of Bombinator' (toad). Slide shows tinted diagram of 'Cross-section through larva of Bombinator' (toad). Part of the left side of the larva is tinted blue on slide. Title below image reads 'Fig. 36. the same experiment as in Fig. 35. On the operated side no lens has developed. (After Spemann, 1912a.)' Late 19th to early 20th century