A new species of
Volvulina, V. pringsheimii, was isolated from Texas. This species differs from the well-known species of
Volvulina, V. steinii, in having pyrenoids in the vegetative cells, a common gelatinous envelope surrounding the colony, a protoplasmic protrusion on the anterior end of each gamete, and spines on the secondary wall of the zygospore.
This paper is dedicated to Professor Dr. E. G. Pringsheim on the occasion of his 80th birthday.