ON THE EFFECT OF VARIATIONS IN THE TEMPERATURE UPON THE PROCESS OF ARTIFICIAL PARTHENOGENESIS

1. The length of exposure to a solution necessary to produce artificial parthenogenesis of the unfertilized eggs of Asterias and Arbacia varies inversely with the temperature. This applies to all the solutions used, whether they exert a chemical or an osmotic effect upon the egg. But, at the same time, with lower temperatures and longer periods of exposure to the solution, a larger percentage of larvae are formed than at the temperature of the room.2. An increase of temperature to 27° C. liquefies the protoplasm of the Asterias egg, and produces a fragmentation of the nucleus. At 30° C. it was found impossible to produce artificial parthenogenesis in Asterias or Arbacia with any of the solutions used.