When the reproductive phenomena of Alcyonella, as manifested both in gemmation and true generation, are viewed in their proper sequence, they will be found to present a series of acts which admit of an obvious comparison with the class of phenomena commonly known as the “alternation of generations.”

From the fecundated ovum an embryo is produced in the ordinary way after the segmentation of the vitellus. In this embryo, which presents at first the form of a locomotive ciliated sac, sexual organs are never directly developed, but there are produced within it by a process of gemmation the following series of zooids.