450 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



imperati Busk 1884 as the genotype. Harmer (1933:621) makes this 

 a synonym of Schizoretepora and Bassler (1935:194) accepts this cor- 

 rection. 



The generic characters as indicated by Canu and Bassler under 

 Schizellozoon are as follows: "The ovicell is widely open and provided 

 with a semicircular slit. It has neither labial avicularium, nor reteporidan 

 pore. The operculum has a broad thickened border; the proximal edge 

 is not straight. The poster of the aperture bears a wide, little deep sinus." 



Schizoretepora tessellata Hincks, 1878 



Retepora tessellata, O'Donoghue, 1923 :47. 

 Schizellozoon tessellatum, O'Donoghue, 1926:73. 



O'Donoghue recorded this species from five localities in British 

 Columbia but gave no description or figure. It has not appeared in the 

 Hancock collections. A brief digest of Hincks' description follows: 

 Fenestrae elongate, narrow, not so wide as the interspaces ; orifice arched 

 above, lower margin straight, with a small central sinus ; a spine imme- 

 diately above each lateral prolongation of the front wall ; a narrow 

 elongate frontal avicularium directed laterally or proximally; ovicell 

 immersed, subglobose, smooth, hollowed out in front ; the most marked 

 peculiarity is the tessellated dorsal surface, covered with great numbers 

 of pointed avicularia similar to those on the front. 



The species has no labial avicularium, no labial pore and no fissure 

 or labellum on the ovicell. 



Genus SCHIZOTHEGA Hincks, 1877 



"Zoarium encrusting; zooecia with a suborbicular (primary) aper- 

 ture, the lower margin slightly sinuated ; secondary aperture raised, 

 tubular, notched or dentate in front ; ooecium terminal, with a fissure 

 in the front surface ; avicularia borne on distinct areas and distributed 

 among the cells, sometimes wanting. Type Lepralia fissa. Busk" (Hincks 

 1877:528). 



The original description of the genus by Hincks will have to be 

 amended to include certain other species, as S. fissure lla Hincks, 1882, 

 has the ooecial fissure closed proximally and a small labellum, giving an 

 appearance like that of Reteporellina, and in S. umbonata new species, 

 described below, there is a labial (suboral) avicularium asymmetrically 

 placed close to the primary aperture. I find no mention of a beaded 

 vestibular arch but in S. umbonata new species the arch is minutely 

 beaded. 



