NO. 9 TERTIARY BRYOZOA CANU AND BASSLER 25 



Measurements. — 



r//a = o. 1 5-0. 1 7 mm fL^cr^o.So mm 



Aperturei , „ Zooecium<^ , 



^ ]la= O.I/ mm 1 /s'^ 0.50-0. 5 5 mm 



Number of zooecia in 4 mm^ 1 1 . 



Occurrence. — Balcombian beds at Muddy Creek, Victoria. 



Holotype.—V.S.^.M. no. 85861. 



CHIASTOSELLA Canu and Bassler, 1934 



CHIASTOSELLA LAMELLATA, n. sp. 



Plate 6, fig. 8 



Description. — The zoarium is free and lamellar ; the fronds are 

 more or less wide, bifurcated. The zooecia are little distinct, vaguely 

 separated by a white line irregularly placed between the areolar pores, 

 elongated ; the frontal is narrow, bordered by two scattered rows of 

 areolar pores concealing the little apparent pleurocyst. The aperture 

 is semicircular ; the proximal border is rectilinear and notched by a 

 straight, short sinus rounded at its extremity; the peristome is thick, 

 little salient, with four or five large distal spines. The ovicell is large, 

 embedded in the distal zooecium, hyperstomial, not closed by the 

 operculum ; the ectooecium is large, circular, convex, smooth, orna- 

 mented on the periphery with lines of small pores arranged radially. 

 The two avicularia are arranged transversely on the transverse median 

 axis of the zooecium ; they are long and thin with pivot, very pointed, 

 projecting on the adjacent zooecia ; their base is placed on the exterior 

 line of areolar pores. 



Measurements. — -x 



r/;a = 0.1 5 mm „ . f^ ^ ^ 



Aperture-^ , Zooecium-^ L^=: 0.60-0. os mm 



^ 1 /a = 0.10-0.12 mm 1 ^ 



Number of zooecia in 4 mm^ 16 to 20. 



Occurrence. — Balcombian beds at Muddy Creek, and Janjukian at 



Mount Gambler, Victoria. 



Cotypes. — U.S.N.M. nos. 85630, 85631. 



CHIASTOSELLA GIBBERA, n. sp. 



Plate 6, fig. 2 



Description. — The zoarium is unilamellar. The zooecia are little 

 distinct, elongated, irregular ; the frontal is convex, ornamented with 

 a longitudinal, median gibbosity surrounded by a double row of 

 scattered areolar pores often separated by pseudocostules. The aper- 

 ture is semielliptical, transverse ; the proximal border is somewhat 

 concave and bears a very narrow linear sinus ; the peristome is non- 



