Is blastomyces a yeast?

So in science we're doing microbiology and we have to find out about different diseases caused by the three different groups of microbes. So for my fungal one I chose blastomycosis and I want to know whether the bacterium that causes it: blastomyces dermatitidis is a mushroom, a mould or a yeast. Research I have done suggests it's a yeast, but nothing seems to straight out say what kind of fungus it is. So could anyone please tell me.