Floral structure in the marine angiosperms Cymodocea serrulata and Thalassodendron ciliatum (Cymodocea ciliata)

Several female flowers were found on plants of Cymodocea serrulata collected in Mida Creek, Kenya, during August 1969. The structure of the female inflorescence of C. serrulata , previously known only from one fragmentary example, is described and shown to be very similar to that of C. angustata Ostenf. but different from that of Thalassodendron ciliatum. The occurrence of small squamulae intravaginales in all leaf and bract axils in both C. serrulata and T. ciliatum is described. Secondary male flowers were observed in the axil of the penultimate bract of about 10% of male inflorescences of T. ciliatum collected on the Kenya coast. The frequency of flowering and the factors affecting flowering in C. serrulata are discussed.