BRYOZOA OF THE PHILIPPINE REGION 161 



MACROPORA CENTRALIS MacGillivray, 1895 



Plate 18, fig. 4 



1S95. Macropora centralis MacGillivray, Tertiary Polyzoa of Victoria, Trans- 

 actions Royal Society of Victoria, vol. 1, p. 55, pi. 8, fig. 3. 



1909. Macropora centralis Levixskn, Morphological and Systematic Studies 

 upon the Cheilostomatous Bryozoa, p. 163, pi. 7, fig. 1. 



Measurements. — 



~ . [7to = 0.20 mm. „ , [ £2 = 0.90 mm. 



Opesium 7 . OD Zooecia , _ nn 



^ I to = 0.28 mm. Its = 0.90 mm. 



Levinsen thinks that Monoporella crassatina Waters, 1882, is iden- 

 tical with this species. Our specimen was dead. It corresponded 

 closely with the figure of Levinsen, 1909. 

 Occurrence. — 



D. 5574. Simaluc Island, south of Tawi Tawi; 5° 30' 45" N.; 



120° 07' 57" E.; 340 fathoms. 

 D. 5577. Mount Dromedario, Tawi Tawi; 5° 20' 36" N.; 119° 

 58' 51" E.; 240 fathoms; crs. S.; 12.4° C. 

 Geographic distribution. — Pacific Ocean: Wanganui. 

 Geologic distribution. — Miocene of Australia (MacGillivray). 

 Plesiotype — -Cat, No. 7963, U.S.N.M. 



Family SETOSELLIDAE Levinsen, 1909 



The ovicell is endotoichal and placed at the distal extremity of the 

 zooecium. 



The known genera of this family are: Setosella Hincks, 1877, 

 Crateropora Levinsen, 1909, and Entomaria Canu, 1914. 



Levinsen, 1909, grouped in this family the species provided with 

 a polypidian lamella, that is to say with a very elementary rudiment 

 of a polypide tube but we have seen that the latter have ve^ different 

 ovicells and can not be placed in the same family. There is no 

 ovicell in Labioporella (Steganoporellidae), an endozooecial one in 

 Caleschara (Microporidae), hyperstomial in Monoporella (Aspidosto- 

 matidae) and endotoichal in Setosella. 



The presence of the polypidian lamella indicates perfection in the 

 hydrostatic system of the hypostega or more exactly, a special rela- 

 tion between the system and the extrusion of the tentacles. Setosella 

 in which opesiular muscles are placed lower, accommodates itself to 

 great oceanic depths, for it has been observed as deep as 1,200 meters. 

 Crateropora with its opesiular muscles placed close to the aperture 

 does not descend below 385 meters. In comparing Rectonychocella 

 and Velumella we have made similar observations. 



Genus SETOSELLA Hincks, 1877 



The endotoichal ovicell is closed by the operculum. Two opesiules 

 placed very low. Vibracula occur. 



Genotype. — Setosella mlnerata Busk, 1860. Recent. 



