Note 236 — VI. ON THE NUMBER OF POLAR BODIES AND THEIR SIGNIFICANCE IN HEREDITY.

The most recent example of this kind is afforded by the excellent work of O. Schultze, ‘Ueber die Reifung und Befruchtung des Amphibieneies,’ Zeitschr. f. wiss. Zool., Bd. XLV. 1887. Schultze has proved that two polar bodies are expelled from the egg of the Axolotl and of the frog, although all previous observers, including O. Hertwig, had been unable to find them. Thus the latter authority states as the result of an investigation specially directed towards this point, that the nucleus is transformed in a peculiar manner (‘Befruchtung des thierischen Eies,’ III. p. 81).