SUMMARY
A new species of Achlya has been described under the name Achlya Sparrowii. Among the species of Achlya with centric or slightly subcentric oospores, androgynous antheridia and smooth oogonial walls there are only two, A. racemosa and A. polyandra, which closely resemble this fungus. A. Sparrowii may be distinguished from A. racemosa quite readily by its much larger oospores, from A. polyandra by its slightly larger, fewer oospores and the usually fewer, only rarely branched antheridial stalks with antheridia applied to the oogonia by the tip rather than laterally. The effect of growth in pure culture on liquid and solid media and of common laboratory temperatures on these characters has been described.