BRYOZOA OF THE PHILIPPINE REGION 131 



The species of this genus did not live in very deep waters but 

 lived from preference at depths of 30 to 60 meters. Only the robust 

 D. ogivalina with opesiular muscles placed very low could live up to 

 170 meters. The temperature observed, 17.2° and 24.2° C, did not 

 seem to influence their life. 



Species of VelumeUa are, on the contrary, bryozoa of the high sea. 

 The only anatomical difference between the two genera is that of 

 their avicularia. Very powerful, much developed, and quite com- 

 plete in VelumeUa, they are very minute and elementary in Dacryo- 

 nella. It must, then, be supposed that the onychocellaria are organs 

 for adaptation to great depths and to bathymetric variations. 



Dacryonella is a special genus of the equatorial zone. 



The known species of this genus are : 



Dacryonella (Reptescharinella) transversa D'Orbigny, 1852 Cretaceous. 



Dacryonella (Homalostega) vespertilio Marsson, 1887 Cretaceous. 



Dacryonella (Homalostega) pavonia Marsson, 1887 Cretaceous. 



Dacryonella octonaria Canu and Bassler, 1920 Eocene. 



Dacryonella octonaria minor Canu and Bassler, 1920 Eocene. 



Dacryonella ogivalis Duvergier, 1921 Miocene. 



Dacryonella ogivalina, new species Recent. 



Dacryonella (Membranipora) minor Hincks, 1885 Recent. 



Dacryonella trapezoides, new species Recent. 



Dacryonella subvespertilio, new species Recent. 



Dacryonella typica Canu and Bassler, 1928 Recent (Mexico). 



DACRYONELLA MINOR Hincks, 1885 



Plate 13, Figs. 9-12 



1881. Membranipora trifolium var. minor Hincks, Annals and Magazine of Natu- 

 ral History, ser. 3, vol. 6, p. 19 (sep.) pi. 11, fig. 6. 



1885. Membranipora trifolium var. minor Hincks, Annals and Magazine of Natu- 

 ral History, ser. 5, vol. 15, p. 299 (sep. 147), pi. 8, fig. 7 



Measurements . — 



SMALL ZOOECIUM 



~ . fk = 0.15mm. ry . fZ2 = 0.35 mm. 



Opesium, _,, Zooecium , _ nr 



[lo = 0.11 mm. [62 = 0.25 mm. 



LARGE ZOOECIUM 



~ . f7i.o = 0.25 mm. „ . fig = 0.45 mm. 



Opesium 7 _ on Zooecium, OA 



r Uo = 0.20mm. Us = 0.30 mm. 



Affinities. — On the same zoarium there are both large and small 

 zooecia according to the irregularities of the substratum. The large 

 zooecia are in the hollows and the small ones on the elevations. The 

 large zooecia have a small cryptocyst as figured by Hincks (1885), 

 while the small zooecia have a large cryptocyst (Hincks, 1881). 

 It may therefore be possible that contrary to the opinion of Waters, 

 1898, all of Hincks specimens belong to the same species. 



