Observations of the gemmae of 135 specific and subspecific taxa of Calymperes, Mitthyridium, and Syrrhopodon reveal that the gemmae of most taxa have a generalized morphology. However, the morphologies of some of the gemmae differ among species and species-groups, revealing evolutionary divergence at the levels of genus and subgenus, in which gemmae vary in shape, color, surface texture, appendages, and in average size (from about 75 μm long in S. orientalis to more than 1,600 μm long in S. helicophyllus). Divergence from the generalized gemma morphology reflects the ecological life styles of the taxa, as for example in Syrrhopodon subg. Pseudocalymperes, in which filiform or moniliform gemmae borne in splashcups correlate with the commonly ramicolous habitat.