This species and _S. clementis_ are referred to _Stratospongilla_ with some doubt. Their gemmules are intermediate in structure between those of that subgenus and those of _Euspongilla_. In _S. sinensis_ the gemmules are packed together in groups at the base of the sponge, and their spicules are smooth, stout, and gradually pointed. V. _S._ (_Stratospongilla_) _clementis_*, Annandale (Philippines). P. U.S. Mus. xxxvi, p. 631 (1909). The gemmules are single and closely adherent at the base of the sponge. Their spicules are very slender and minutely spined. VI. _S._ (? _Stratospongilla_) _coggini_*, Annandale (W. China). Rec. Ind. Mus. v, p. 198 (1910). The gemmules apparently lack microscleres. They resemble those of _S. clementis_, to which the species is probably related, in other respects. The skeleton-spicules are spiny and rather stout, the species being strongly developed at the two ends. VII. _S._ (_Stratospongilla_) _sumatrana_*, Weber (Malay Archipelago). Zool. Ergebnisse einer Reise in Niederländisch Ost-Indien, i. p. 38 (1890). Closely allied to _S. indica_ (p. 100) but with pointed skeleton-spicules. VIII. _Ephydatia fortis_, Weltner (Philippines). Arch. Naturgesch. lxi(i), p. 141 (1895). This species is remarkable for the great development of the spines on the shaft of the gemmule-spicules. IX. _Ephydatia bogorensis_*, Weber (Malay Archipelago). Zool. Ergebnisse einer Reise in Niederländisch Ost-Indien, i, p. 33 (1890). The gemmule-spicules have rather narrow flattish disks, the edge of which is feebly but closely serrated. X. _E. blembingia_*, Evans (Malay Peninsula). Q. J. Microsc. Sci. London, xliv, p. 81 (1901). The gemmules resemble those of _Dosilia plumosa_ but are spherical. There are no free microscleres. XI. _Tubella vesparium_*, v. Martens (Borneo). Arch. Naturg. Berlin, xxxiv, p. 62 (1868). Closely related to _T. vesparioides_ (p. 189), but with spiny megascleres. As regards _Spongilla decipiens_*, Weber, from the Malay Archipelago, see p. 97. II. HISTORY OF THE STUDY OF FRESHWATER SPONGES.