In the following pages sorne account is given of 20 species of Nemerteans from the Eastern Indian Ocean. In addition to those collected by the Percy Sladen Expedition, we bave been able to examine a collection made by Mr. Oyril Crossland at and near Zanzibar, and also a few procured by Professor Herdman from Ceylon. To these two gentlemen we desire to express our thanks. Other specimens reached us besides those described below, but owing to their imperfect condition or to their unsatisfactory preservation we have not included them in our account. [NOT CONTROLLED OCR]