BRYOZOA OF THE PHILIPPINE REGION 139 



a convex frontal more or less finely perforated. This character does 



not appear to correspond to a difference of any important function. 



Also in our opinion it would be convenient to combine Selenaria and 



Vibracella and to consider the latter simply as a division of the genus 



developed in the Northern Hemisphere up to the Pliocene. The 



branch with cribrimorph vibracula (Selenaria) arose in the southern 



seas and still exists in the equatorial zone and has never crossed the 



Equator. 



Genus MONSELLA Canu, 1900 



The zoarium is articulated and radicellate. The polypidian lamella 

 is very long; the opesiules are very long linear slits. The opesium is 

 orbicular. The avicularia are arranged in all the interzooecial angles. 



Genotype. — Monsella (Planicellaria) eocena Pergens, 1886. Eocene 



(Montian). 



Genus ANDREELLA Jullien, 1888 



The cryptocyst is complete; it is perforated laterally by an opesiule 

 in the form of a cross. The opesium is semilunar with a proximal 

 border more or less concave. The avicularia are constant and epi- 

 zooecial. 10 tentacles. 



Genotype. — Andreella (Micropora) uncifera Busk, 1884. Recent. 



In Micropora the muscular fibers unite their tendons into a single 

 one in order to traverse a small opesiule. The reunion is not made in 

 Andreella. Moreover the avicularia are here constant and not spo- 

 radic. These differences do not appear to be of generic order to recent 

 authors and they consider Andreella as a subgenus of Micropora. 



Family CALPENSIIDAE Canu and Bassler, 1923 



This family and the seven genera referred here have been de- 

 scribed and illustrated in our Late Tertiary Monograph of 1923. 



Genus MICROPORINA Levinsen, 1909 



MICROPORINA JAPONICA. new species 



Plate 14, figs. 9-11 



Description. — The zoarium is articulated; each segment is narrowed 

 at the base and formed of 10 longitudinal rows of cells. The zooecia 

 are distinct, united by their mural rim or separated by a furrow, 

 very elongated, rectangular; the mural rim is thick, smooth, rounded, 

 very salient; the cryptocyst is deep, flat, covered by a multitude of 

 small tremopores, and elevated above in order to form the inferior 

 lip of the opesium. The opesium is small, transverse, semielliptical. 

 The two opesiules are large and placed in the vicinity of the opesium. 

 The avicularium is placed at the base of each zooecium; it is oval, 

 with pivot, with the beak turned towards the base. 



