On leaves, petioles and stems of Tillaea erecta [Crassula connata] ...

This species [induces] large, protruding composite sporangial and resting spore galls. The larger part of the gall consists of the greatly enlarged infected cell which may be oval to subspherical in shape ... [The] sheath of healthy cells [around it] are elongate, somewhat diamond-shaped and slightly eurved [and may be] filled with a more or less homogeneous substance which stains deeply in prepared slides and gives the galls a very dark chromatic color ...