160 U.S. NATIONAL MUSEUM BULLETIN 272 



Discussion. — Drulia batesii is clearly distinct from D. hrowni by- 

 its gemmiilar characteristics and by its prolific abundance of free 

 and gemmular microscleres. Although these criteria permit an easy 

 separation of both on a specific level, their use for generic differentia- 

 tion, i.e., Drulia Gray and Parmula Carter, is fully unjustified. Both 

 species seem to be the extremes of an intergrading series of species, 

 aU in urgent need of detailed revision. It is hoped that the extremely 

 neglected spongillid fauna of Latin America will be studied more 

 comprehensively, resulting in a better understanding of the species 

 involved. 



