A number of hybrids obtained by fusion of protoplasts of complementary auxotrophic strains of Candida albicans were analysed for growth rates, cell volume, DNA content, stability and adherence to human buccal epithelial cells. SDS-PAGE analysis of the cell wall proteins indicated that the hybrid cell walls contained many more of the proteins associated with one parent than the other. The adherence values of the hybrids were closest to the parent with which they shared most cell wall proteins and it is suggested that the hybrids contain the genome of this parent along with one or more of the chromosomes of the other.