Self-fertilisation in Mollusca

Abstract

As the question of self-fertilisation in the more highly organised invertebrates is of considerable importance from the genetic point of view, I would like to direct the attention of readers of NATURE to a publication (Acta Soc. pro Fauna et Flora Fennica, vol. 40, No. 2, 1915), a copy of which I have just received from the author, Dr. A. Luther. It constitutes an important addition to the evidence for the occurrence of self-fertilisation in mollusca, as Dr. Luther states that he succeeded in rearing two generations by selffertilisation in Agriolimax agrestis. I have recently pointed out (Proc. Malac. Soc., vol. 14, 1921) the value of Kunkel's work on Arion in this respect; but at the time Dr. Luther's results were not known to me, as the publication was not available and had not figured in the “Zoological Record”. Should these important observations be finally confirmed and the technique improved so as to produce more than two generations, a very valuable contribution to genetic study will be achieved. Dr. Luther's work, however, emphasises the necessity for conducting a study of environmental conditions in order to secure improved viability.