O NE COMPLETE POLYCHAETE SPECIME N and two fragments collected by E. F. Ricketts in 1940 from Cape San Lucas, Lower California, are described here as members of a new species. The indi viduals concerned were taken from-the . tubes of Spirobranchus incrassatus March, a serpulid polychaete. The new species resembles other polydorids in some charact eristics, but is significantly different from all known species; the differences are discussed below.
