372 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



Geme.llipora polita MacGillivray, 190-1. 



Gemeltipora auriculata Maplestone, 1901. 



Under the name of GemdUpom, Sinitt has described two sorts of apertures. 

 The first species described belongs to the genus Pasythea Lamouroux, 1812. The 

 orifice of GemcUipora glabra is the one which has been considered as typical. In 

 1904. Waters gave a list of species of this genus; but it will be necessary to redis- 

 tribute them into the genera SchizomaveUa and Ti*ypostega. 



GEMELLIPORELLA, new genus. 



The ovicell is hyperstomial and deeply embedded in the distal zooecium. The 

 operculum does not close the ovicell and operates in a locella. The form of the 

 aperture is like a keyhole. The frontal is garnished with lateral areolar pores 

 and with a granular pleurocyst. 



Genotype. Gemelliporella vorax, new species. Kange : Miocene, Pliocene. 



The genus Gcm-cllipora Smitt, 1872, comprised species with both a tremocyst 

 and a pleurocyst; we group the latter in this new genus. The type species will be 

 described in a forthcoming volume. 



Genus NIMBA Jullien, 1903. 



1903. ^'iitibn JULLIEN, Bryozoaires provenant des eampagnes de I'Hirondelle, Monaco, p. 93. 



The frontal is smooth or granular. The orifice is semilunar, with a rimule 

 on the poster which is almost entirely formed of two large cardelles. which the 

 rimule separates ; the anter is smooth ; the peristome forms a sort of aureola around 

 the orifice, and the globular ovicell occupies the anterior region of the aureola. The 

 opening of the ovicell is always closed by the operculum, which must lower itself 

 to give passage to the larvae. (Translation after Jullien.) 



Genotype. Nimfia praetexta Jullien, 1903. Recent (Azores). 



Genus CHARACODOMA Maplestone, 1900. 



1900. Characodoma MAPLESTONE, Further descriptions of the Tertiary Polyzoa of Victoria, 

 pt. 4, Proceedings Iloyal Society of Victoria, vol. 13 (n. s.), pt. 1, p. 7, pi. 2, fig. 17. 



" Zoarium in elongated quadrate internodes. Zooecia uniserial on each face 

 of the zoarium. Apertura ovate with a sharp denticle on each side pointing down- 

 ward over the lower or distal triangular portion." (Maplestone.) 



Genotype. Characodoma halli Maplestone. 1900. Miocene of Australia. 



Group 2. HIPPOPOKAE Canu and Bassler, 1917. 

 (LEPRALIIDAE Jullien. 1903.) 



Anatomical bibliography. 1865. SMITT, Om Hafs-Bryozocrnas utvekling och fett kroppar Ofver- 

 sight, Kongl. Veteuskaps-Akadeniiens Forhamllingar, vol. 22. pp. 7, 28, pi. 1, figs. 11, 12; pi. 2, 

 fig. 1. pi. 5, figs. 20-22. 1877. BARBIOS, Reeherches sur IVuibryologie des Bryozoaires, Trav.iux 

 de 1'Institut de Zoologie de Lille, fasc. 1, pi. 7, figs. 9, 13, 17, and 20. 1900. CALVET, Contribu- 

 tion a 1'histoire uaturelle des Bryozoaires ectoprocfps marins, Montpellier, pi. 0. 1903. HARMER, 



