A new species of the genus Bullera derx.

A new yeast species, Bullera piricola, is described. The three strains studied were all isolated from the pear phylloplane. This species differs from all Bullera species known at present by forming symmetrical as well as asymmetrical ballistospores. The problem of its integration into the genus Bullera Derx is discussed. An amended diagnosis of the genus Bullera is given.