BRYOZOA OF THE PHILIPPINE REGION 309 



Variations. — The general characters noted by Waters are quite 

 visible on our specimens. The apertura is buried at the bottom of 

 the peristomie; the rimule is rectangular and is visible only by inclin- 

 ing the preparation. But there are some slight differences, notably 

 the micrometric dimensions are somewhat larger, the ovicell has a 

 perforated frontal area, the frontal avicularia are smaller and often 

 arranged symmetrically and finally the internal armature of the 

 operculum is triangular. Our specimens are unilamellar and not 

 encrusting. 



We have a specimen from Sydney furnished by Miss Jelly which 

 corresponds well to Water's figure although the frontal surface is 

 granulated as in ours, and the zooecia are narrower than ours. 



In the interior, the rimule is placed between two small tuber- 

 osities. The operculum is very thin and difficult to prepare; its 

 structure is quite identical with that indicated by Waters but its 

 form is different. The operculum closes the ovicell. 



Waters stated that he did not know into what genus to class his 

 species but we believe Lacerna is correct. 



One of the frontal avicularia may become very large and spatulate 

 as in Smittina trispinosa. 



Biology. — Our specimens were in reproduction May 5, 1908 (340 

 meters). They occur in deep waters (340-970 meters). Those from 

 Mompog were dead and encrusting. 



Geographic distribution. — Sydney and Green Point, Port Jackson, 

 Australia. 



Occurrence. — 



D. 5173. Jolo Light, Jolo; 6° 02' 55" N.; 120° 53' E.; 186 



fathoms; Sh., co. 

 D. 5219. Mompog Island, between Marinduque and Luzon; 13° 

 21' N.; 122° 18' 45" E.; 530 fathoms; gn.M.; 10.4° C. 



Plesiotypes.— Cat. No. 8131, U.S.N.M. 



Genus GEMELLIPORELLA Canu and Bassler, 1920 



GEMELLIPORELLA AREOLATA, new species 



Plate 34, figs. 5, 6 



Description. — The zoarium encrusts shells, nullipores and Orbito- 

 ides. The zooecia are distinct, separated by a furrow, elongated, 

 deformed by an enormous oral avicularium with denticles or with 

 pivot; the frontal is convex, and formed by a granular pleurocyst 

 surrounded by areolar pores more or less large. The apertura is 

 largo, much elongated, triangular, with a small rimule. Tho ovicell is 

 globular, buried in the distal zooecium, of the same nature as the 

 frontal. 



Measurements. — 



Aperturaj^ - 14 " - 10 ™- Zooeciaj^ - 40 " - 50 mm ' 



ua =0.10 mm. Xlz =0.35-0.45 mm. 



2182—29 21 



