Slide showing table concerning the 'Gastrulae of Amblystoma mexicanum.' Slide shows table concerning the 'Gastrulae of Amblystoma mexicanum' salamander (Axolotl). The contents of the table are as follows: 'Blastula roof = 0.75 R.Q.; Half-moon yoke-plug gastrula: dorsal lip region = 1.0 R.Q., ventral ectoderm = 0.83 R.Q.; Three-quarter-moon yoke-plug gastrula:dorsal lip region = 1.0 R.Q., ventral ectoderm = 0.89 R.Q.; Closing nerual folds of young neurula = 1.0 R.Q.' Late 19th to early 20th century