A MONOGRAPH OF THE TERTIARY POLTZOA OP VICTORIA. Ill 



Family Reteporid^e. 



Zoariuni calcareous, erect, foliaceous, fenestrate, reticulate or ramose, originating 

 from a contracted base. Zooecia oblique, closely united or immersed, indistinct 

 posteriorly. 



Retepora, Iniperato. 



Zoarium usually fenestrate or reticulate, rarely simply brancbed ; posterior 

 surface vibicate. 



1. B. beaniana, King. PL XV., figs. 7, 8. 



B. beaniana, Busk, B.M.C., Pt. II., 94; Crag. Pol., 75; Hincks, B.M.P., 391; 

 Waters, Q.J.G.S., 1883, 319. 



Zoarium fenestrate. Zooecia separated by narrow raised lines, ovate, slightly 

 convex, projecting slightly forwards above ; surface smooth or with irregular small 

 depressions ; thyrostome arched above, straight below, each side of the peristome 

 forming an acute process ; an elevation on the lower lip surmounted by a nearly 

 circular avicularium, the semicircular mandible directed downwards and forwards, 

 the upper edge of the avicularium produced into a sharp spine ; on the front of the 

 zooecia, towards the upper part, frequently an elliptical avicularium, with the 

 mandible pointed straight or obliquely downwards. Dorsal surface divided angularly 

 by sharp vibices, smooth, and with scattered elliptical avicularia. 



S.P. Recent Europe. Crag., England. 



This species, although well known in Europe, has not as yet been found living 

 in Australia. 



2. B. fissa, McG. PL XV., figs. 9, 10. 



B. fissa, McG., T.R.S.V., 1869 ; id., P.Z.V., p. 95 ; B. marsupiata, Smitt, 

 Eloridan Bryozoa, Pt. II., 67 ; Waters, Q.J. G.S., 1881, 342 ; id., var. niucronata, I.e., 

 1883, 439. 



Zoarium fenestrate. Zooecia elongated, rhomboidal or ovate, separated by 

 distinct raised margins ; thyrostome (primary) hollowed or straight below, the peri- 

 stome largely developed ; the secondary aperture projecting upwards and forwards, 

 a slight sinus in lower lip, from which extends downwards a narrow groove, 

 frequently closed in front, especially in the lower part, to form a tube ; at the end 

 of this groove or tube frequently a small pore ; an avicularium to one side or below 

 the extremity of the groove, with the mandible directed straight or obliquely down- 

 wards ; occasionally other avicularia on the front of the zooecia. Ooecium rounded, 

 with a vertical slit wider above. Dorsal surface divided by narrow vibices, smooth 

 or finely granular, and occasionally with a few scattered avicularia. 



