38 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 93 



orbicular ; its proximal border bears a wide lyrule, salient and flat. 



In front of the aperture on the median longitudinal axis of the zo- 



oecium, there is a large orbicular perforation corresponding to an 



avicularium of the same form. 



Measurements. — - 



(ha — 0.14 mm . fLc — 0.6^ mm 



Aperture-'. , Zooecium-^ , ^ ^ 



i I /a = 0.1 2 mm 1 /.o' = o.4i mm 



Number of zooecia in 4 mm', 13. 



Occurrence. — Balcombian beds at Muddy Creek, Victoria. 



Holotype.—U.S.N.M. no. 85868. 



SMITTINA (?) PARVIOVICELLOSA, n. sp. 



Plate 7, fig. 4 



Description. — The zoarium is free, bilamellar, with wide, flat, or 

 undulated fronds. The zooecia are distinct, separated by a salient 

 thread, much elongated, fusiform ; the frontal is convex, surrounded 

 by small and very numerous areolar pores and formed by a rugose 

 pleurocyst. The aperture is elliptical, transverse, without peristome. 

 The ovicell is very small, globular, smooth, placed on the distal zo- 

 oecium. The oral avicularium is small, adjacent to the aperture, el- 

 liptical, with pivot, placed on the median longitudinal axis of the 

 zooecium. 



Measu rem e n ts. — • 



(ha = 0.10 mm f Lxr = i .00- 1 . 24 mm 



Aperture-^ , ^ Zooecuuu-^ , , ^ 



^ 1 la — O.i^ mm 1 /.cr = 0.30-0.30 mm 



Number of zooecia in 4 mm', 12. 



Occurrence. — Janjukian beds at Orbost, Gippsland, Victoria. 



Holotype.— U.S.N. M. no. 85869. 



MUCRONELLA Hincks, 1880 

 MUCRONELLA ELONGATA, n. sp. 



Plate 7, fig. 6 



Description. — The zoarium is free, cylindrical, rectilinear, of small 

 diameter (0.80 mm). The zooecia are distinct, separated by a small, 

 little salient thread, very long, narrow, fusiform. The frontal is 

 convex, smooth, surrounded by a row of 14 to 16 pairs of very small 

 areolar pores. The peristome is salient, thin, elliptical, elongated ; its 

 proximal border bears a small mucron inclined in the peristomie; 

 the aperture is visible at the bottom of the peristomie. The ovicell is 

 large, salient, globular, placed on the distal zooecium, smooth, hyper- 

 stomial, opening in the peristomie. 



