BRYOZOA OF THE PHILIPPINE REGION 351 



is convex, smooth or rugose. The apertura is oval, elongated; the 

 peristome is very salient, complete, thin, with two distal spines, a 

 proximal pseudorimule and two lateral very salient lips; the lyrula 

 is broad but little salient; the two cardelles are quite minute. The 

 ovicell is small, globular, rugose. Two small triangular, ascendant 

 avicularia are located near the peristome on each side of the apertura. 

 One of these is sometimes transformed into a large spatulate avicu- 

 larium with much enlarged beak. 

 Measurements. — 



Apertura!^ =°- 14 mm ' Zooeciajf 2 =0.50-0.85 mm. 



Ua =0.12 mm. \lz -0.60-0.75 mm. 



Variations. — The ancestrular zooecia are very small. The median 

 zooecia are elongated and much larger; the marginal zooecia are 

 quite large and wide, transverse. The initial zooecia (serialogene) 

 of a series are also quite wide. 



The two oral avicularia are rather constant but they disappear 

 sometimes. The large spatulate avicularium is rare. Small sporadic, 

 elliptical avicularia directed downward appear either on the frontal 

 or on the line of areolar pores. 



Affinities. — This species differs from Smittina trispinosa var. 

 bimucronata Hincks in the presence of two oral avicularia adjacent 

 to the two lateral lips. 



Biology. — This species presents some interesting features. The 

 zoarium creeps over the sea bottom; its small fronds surround speci- 

 mens of Globigerina and unite them together. The small avicularia 

 do not appear by chance but they are always placed close to the 

 aperture of an adjacent zooecium. This observation shows that the 

 avicularia are in intimate relationship with the tentacular life of the 

 polypide and with the function of the operculum. Moreover it 

 proves again the biologic unity of the zoarium. The zooecia are not 

 isolated organisms sufficient unto themselves but they serve one 

 another, appearing to obey some central organ. 



The species was in reproduction and fixation in February and May, 

 1908 (183-294 meters). It inhabits the great depths. The little 

 complexity of the mandibles should be in harmony with the tran- 

 quility of the water. 



Occurrence. — 



D. 5135. Jolo Light, Jolo; 6° 11' 50" N.; 121° 08' 20" E.; 161 



fathoms, fine co. S. 

 D. 5255. Dumalag Island, Gulf of Davao; 7° 03' N.; 125° 39' E.; 

 100 fathoms, sft. M. 



Cotypes— Cat. No. 8130, U.S.N.M. 



