1. The spermatozoid of Selaginella involvens SPR. consists of the nuclear part, the cilia-bearing part, two long cilia, the posterior appendage which is composed of three grains and the little process at the posterior end of the body. 2. Two long cilia are attached to the top of the cilia-bearing part having a common basal swollen point, but the basal portion of one of the cilia is a very fine thread and sticks fast to the cilia-bearing part. 3. The spermatozoid runs quickly along an irregular course, rotating in a left-handed direction. 4. The spermatozoid of Isoetes japonica AL. BR. is spiral-shaped of about two coils and consists of the nuclear part, the plasmic band, the border brim the cilia-bearing part and the cilia. The velocity of the movement is 0.079-0.183mm/sec. in the active state. The length of the extended spermatozoid is about 33.3μ. 5. Besides the plasmic band which runs along the whole length of the spermatozoid the fin-like appendage can also be seen. 6. The cilia-bearing part is almost triangular occupying the anterior part of the spermatozoid and bordered by the border-brim with the exception of the neck-part. 7. The nuclear part begins at the neck-part and reaches to the posterior end of the spermatozoid. 8. Most of the spermatozoids have eleven cilia attached to one surface of the cilia-bearing part. Three cilia out of eleven stretch forwards and the remaining eight go rearward. 9. The spermatozoid of Salvinia natans HOFFM. is made up of the border-brim, the plasmic band, the nuclear part and the cilia. 10. The border-brim runs along the upper edge of the plasmic band and reaches to the posterior end of the plasmic band which occupies about 415 of the anterior part of the spermatozoid. 11. The cilia grow in one row, from the upper surface of the plasmic band, having basal swollen points at their bases. 12. The number of cilia are counted in 238 spermatozoids, the mean value being 19.2. 13. The direction of the. coils of the spermatozoid is the same with that of the rotation and is right-hand. The speed of the movement is 0.13-0.18mm/sec. The writer wishes to express his best thanks to Dr. SINOTô for his valuable suggestions and criticism during the course of this work.