XVI International Botanical Congess
The life history of Dasya caraibica Boergesen was examined in culture and observed to be of the Polysiphonia-type. Plants developed initially as monosiphonous filaments and subsequently produced polysiphonous axes. Cellulosympodial division was initiated after 5 days. Pericentral cell initiation did not occur until 13 days when the alga had reached a height of 1.0-1.4 mm. The pericentral cells were originally cut off from an axial cell closely behind the indeterminate apex. Pericentral cell development sequentially proceeded on axial cells proximally towards the base. Gametophytic and tetrasporophytic plants matured in approximately 4 weeks. Dioecious gametophytes were observed in culture with spermatangia developing prior to the appearance of procarps.