152 MONOGRAPH OF THE FOSSIL POLYZOA OF THE 



Aperture large, subquadrate, angles rounded, and placed at the end of the cellule ; 

 bordered by a raised and slightly thickened lip, which usually encircles the rest of the 

 cellule, and the special pores. These pores are two in number, elongated, oblique and 

 placed abreast of the mouth. Surface marked by about eleven fossets, those at the 

 proximal end disposed radiately. These cover the lateral two-thirds of the cellule, 

 leaving the middle third solid. Ovarian vesicles subglobular, and encroached on at 

 the mouth so as to be broadly, and sometimes deeply emarginate. 



With cellules resembling Eicharipora Abbottli in form, this species can be distinguished 

 by its being encrusting, by the greater size of the mouth, and the fewer " special 

 fossets." 



From the Cretaceous, near Mullica Hill, N. J. One specimen, Coll. W. M. G. 



We have another species from the same locality, but the only specimen we have 

 seen, is too imperfect to characterize. 



FLUSTRELLARID^, d'Orb. 



BIFLUSTRA, d'Orb. 1852. 



Colony composed of free compressed branches, cellules on both sides, placed back 

 to back. Opening occupying the greater portion of the cellules, closed in the living 

 state by a membranous operculum, through which the mouth is pierced. Mouth 

 closed by a movable lid. Cellules in longitudinal lines and quincunx, juxtaposed. 



With the same mode of growth as Eachara, this genus can be at a glance distin- 

 guished by its Membranipora-like cells. 



B. torta, n- s., fig. 36. — Colony composed of very compressed branches, usually 

 twisted, rarely in the same plane for more than a quarter of an inch. Cellules ar- 

 ranged in longitudinal lines and usually in quincunx. About six to ten rows on each 

 side of the branches, although we have in one case counted twenty just below a bifur- 

 cation. Cellules closely juxtaposed ; elongated oval anteriorly, contracted and after- 

 wards dilated posteriorly, and straight or slightly emarginate at the proximal edge. 

 Opening elongated oval, variable in form and size, occasionally subquadrate, sometimes 

 slightly narrowed posteriorly, either more or less than half the surface of the cellule, 

 no lip or margin, simply pierced in the substance of the cellular wall and placed at 

 the lowest part of the surface. Surface smooth, concave, elevated at the anterior and 

 antero-lateral margins into a rounded or acute edge, a little higher than the posterior 

 portion of the surface of the adjoining cellules. From this edge the surface slopes 

 inwards toward the mouth. Behind the mouth the surface is generally marked by 

 two radiating depressed lines, running from the proximal corners of the mouth to the 

 corresponding corners of the cellule, between which is a rounded elevation, not as 

 high, however, as the anterior end of the preceding cellule. 



