BRYOZOA OF THE PHILIPPINE REGION 405 



Occurrence.— D. 4807. Cape Tsiuka, Sea of Japan; 41° 36' 12" X.; 

 140° 36' E. 



Cotypes.—C&t. No. 8213, U.S.N.M. 



Genus PSILOPSELLA Canu and Bassler, 1927 



The zooecia are large and surrounded by parietal dietellae; the 

 frontal is surrounded with large areolar pores distinct from the 

 dietellae. The aperture is orbicular and buried at the bottom of a 

 long peristomie. 



Genotype. — Psilopsella uniseriata Canu and Bassler, 1927. Recent. 



TSILOPSELLA UNISERIATA Canu and Bassler, 1927 



Plate 57, figs. 1-3 



1927. Psilopsella uniseriata Canu and Bassler, Classification Cheilostomatous 

 Bryozoa, Proc. U. S. Nat. Mus., vol. 69. art. 14, p. 8, pi. 1, fig. 10. 



Description. — The zoarium is uniserial and encrusts pebbles, shells 

 and corals presenting numerous asperities. The zooecia are very 

 large, elliptical; the walls are much thickened and excavated with 

 dietellae opening outward; the frontal is very convex, smooth, sur- 

 rounded by a line of large areolar pores perfectly distinct from the 

 dietellae; the peristomie is large, salient, tubular; the peristome is 

 thick and orbicular. 



Measurements. — 



„ . , . [Am = 0.30 mm. „ . fl2=1.50mm. 



Penstomice , . OA Zooecia, n OA , __ 



\lpi = 0.30 mm. U2 = 0.80-1 .00 mm. 



Affinities. — This species on account of its gigantic dimensions, 

 appeared to us interesting to figure although our specimens were 

 incomplete. The presence of parietal dietellae as in Perigastrella 

 causes us to introduce this genus provisionally in the Phylactellidae. 

 Biology. — This large species never spreads out over a smooth 

 surface but it creeps between the asperities of the substratum and 

 around them in order to take advantage of this shelter. It appears 

 thus to profit from the natural protection formed by the irregular- 

 ities of the body on which the larva is fixed. The quantity of nourish- 

 ment necessary for the construction of a single zooecium is consider- 

 able and it can subsist only in localities enormously rich in diatoms. 

 Our specimens were dead. 

 Occurrence. — 



D. 5137. Jolo Light, Jolo; 6° 04' 25" N.; 120° 58' 30" E.; 20 



fathoms; S. Sh. 

 D. 5217. Anima Sola Island, between Burias and Luzon; 13° 20' 

 N.; 123° 14' 15" E.; 105 fathoms; crs. gy. S.; 17.2° C. 

 Holotyj)e.—C&t. No. 8214, U.S.N.M. 

 2182—29 27 



