The process of spermatoteleosis of Dryopteris oligophlebia C. CHR. var. elegans H. ITÔ was observed in distilled water on vital material. The time taken up by the spermatoteleosis was about 56 hours, during which the spherical spermatid was transformed into a spermatozoid. The time taken up by fertilization was also measured in the present. study. When the prothallia was put in distilled water the fertilization took place in about 100 minutes. The duration of various phases of the process of fertilization were also shown in the present paper.