BRYOZOA OF THE PHILIPPINE REGION 287 



Genus ESCHAROIDES Milne Edwards, 1812 



This genus is very poorly defined. The only recognizable species 

 in it have passed into synonymy in different genera. Those which 

 remain in the second edition of the "Animaux sans vertebres," of 

 Lamarck, have never been figured; the name of Milne Edwards ought 

 to be preserved for them. Moreover in 1836, in his remarkable 

 study on the Eschares, Milne Edwards did not mention Escharoides. 



In 1867, Smitt recognized Escharoides without defining it and classed 

 in it E. sarsi Smitt, 1867, and E. rosacea Busk, 1856. In 1880, 

 Hincks defined the genus, basing it upon the structure of E. sarsi 

 Smitt, 1867, and added E. quinconcialis Norman, 1867. In 1884, 

 Busk followed the classification of Hincks and added E. occlusum 

 Busk, 1884 and E. rerruculata Smitt, 1872. The interpretation of 

 Smitt prevailed up to 1888, when Waters classified E. occulsum in 

 Lepralia. 



In this mixup we do not see what rules of nomenclature can be 

 applied. It may be added that at the Paris Museum the genus 

 Escharoides has never been taken into consideration and D'Orbigny, 

 1852, did not mention it. 



Genus POSTERULA JuIIien, 1903 



The ovicell is concealed, hyperstomial, closed by the operculum. 

 The frontal is an olocyst covered by a much thickened pleurocyst, 

 traversed by much scattered, closed tubules. It is surrounded by 

 large areolar pores separated by short radiating costules. The 

 aperture is orbicular with concave and deep poster, covered by a 

 crescentic operculum, in which the posterior concavity has no rela- 

 tionship to the form of the orifice, leaving the compensatrix widely 

 open. The peristomie is hollowed out in the great thickening of 

 the frontal; its orifice or peristomice bears a pseudorimule surrounded 

 by many avicularia. 



Genotype. — Posterula (Escharoides) sarsi Smitt, 1867. Recent. 



The frontal of the ovicell bears 1 to 4 pores more or less buried 

 according to the thickness of the tubular tissue which envelopes the 

 entire zooecium and its ovicell. The polypide is provided with 16 

 (Waters) or 18 (Jullien) tentacles. "The testicle is diffuse. The 

 spermatozoids disperse and fill the perigastric cavity at their maturity. 

 The ovary placed close to the wall of the endoderm in the perigastric 

 cavity contains many ovules at different stages of development." 



"The operculum is thin and difficult to study, for it is dragged under 

 the influence of dessication to the interior of the zooecium by the 

 tentacular sheath; it includes a very thin foliaceous border surround- 

 ing a central chitinous core in the form of a crescent with rounded 

 ends." (Translation after Jullien, 1903.) The tubules are frequently 

 open (Robertson, 1908, fig. 67). There are oral glands (Waters, 

 1900). 



