Baeolophus is a genus of birds in the family Paridae. Its members are commonly known as titmice. All the species are native to North America. In the past, most authorities retained Baeolophus as a subgenus within the genus Parus, but treatment as a distinct genus, initiated by the American Ornithologists Union, is now widely accepted. The plural of titmouse is a subject of much discussion among ornithologists. Most use titmice, but some insist on titmouses. The reason for this debate is simple. The genus contains the five species: