BRYOZOA. OF THE PHILIPPINE REGION 133 



Affinities. — The distal edge of the mural rim bears sometimes two 

 small avicularia arranged symmetrically. The species differs from 

 Dacryonetta trapezoides in its small interzooecial avicularia, not 

 arranged in pairs on the distal border of the mural rim. It has much 

 resemblance to DacryoneUa minor Hincks, 1885, but its larger micro- 

 metric dimensions are not in accord with the name given by the 

 English author. 



The opesiular indentations are rarely apparent and the opesium 

 is never contracted at the level of articulation of the opercular valve. 

 Our specimens were dead. 

 Occurrence. — 



D. 5144. Jolo Light, Jolo; 6° 5' 50" N.; 121° 2' 15" E.; 19 



fathoms; co. S. 

 D. 5147. Sulade Island, Sulu Archipelago; 5° 41' 40" N.; 120° 



47' 10" E.; 21 fathoms; co. 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. 

 Holotype.— Cat. No. 7935, U.S.N.M. 



DACRYONELLA TRAPEZOIDES, new species 



Plate 14, figs. 2, 3 



Description. — The zoarium encrusts nullipores. The zooecia are 

 distinct, separated by a deep furrow a little elongated, oval, the 

 point above; the mural rim is broad, salient; the cryptocyst is shal- 

 low, somewhat convex, smooth and never surrounding the opesium. 

 The opesium is large, terminal, semielliptical, very little transverse, 

 trapezoid in form. The ovicell is endozooecial, small, convex, smooth, 

 transverse. Two small triangular avicularia are placed on the 

 distal border of the mural rim; the beak is turned towards the median 

 zooecial axis. 



Measurements. — 



Z2 = 0.55 mm. 

 fe = 0.45 mm. 



Structure. — The opercular valve is a transverse arch supported on 

 the interior part of the distal border of the mural rim; it is bordered 

 by a very much thickened sclerite enclosed in a very thin sclerite 

 attached to the ectocyst. This is the usual structure in the Micro- 

 poridae. The dimensions on the same specimen are quite variable. 



At the bottom of the opesium, almost at the level of the hinge of 

 the opercular valve there are two small symmetrical fosettes. 



The place of the opesiular muscles is indicated on the ectocyst by 

 two black points nonsymmetrically located. The opesiular indenta- 

 tions to which they correspond are little deep and very irregular. 

 2182—29 10 



~ . 7io = 0.20-0.22 mm. n 

 Opesium 7 n nn n nr Zooecium 



uo = 0.20-0.25 mm. 



