The fulturae ("compound synapticulae"), their structure and reconsideration of their systematic value

The study of the structure of fulturae in Recent Cycloseds cyclolites and various species of Fungia reveals an upward growth of fibers gradually diverging from the centre outwards. The distal end of each fultura Is rounded and rhythmic secretion leaves a succession of horseshoe figures on the outer surface. In their structure, the fulturae differ basically from "simple" synapticulae and from the design which had been ascribed to them in literature. The twofold notion of synapticulae ("simple" and "compound"), until now considered as fundamental distinctive character for the suborder Fungilda, should be abandoned. The suborder Fungilda, as delineated in recent classifications, seems to include at least two apparent, non-related groups: one common in Tertiary and Recent forms which bear fulturae and show a septal structure similar to the Montlivaltia type (e.g. Cycloseris) and the other including pennular corals (mainly Mesozoic) with or without "simple" synapticulae.