32 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 93 



pores, and formed by a granular pleurocyst. The aperture is large, 



elliptical, transverse, oblique, often mucronated ; the peristome is thick 



and granulated like the frontal. Laterally, on the transverse median 



axis of the zooecium and symmetrically arranged, there are two small 



elliptical, salient avicularia with pivot, oriented proximally. 



Measiirem e n ts. — 



r/;a = 0.1 2-0. 1 5 mm . fL^'^ 0.75-0.80 mm 



Aperture<^ , ^ Zooecia<^ , 



^ I la = 0.20 mm I /.? = 0.40-0.45 mm 



Number of zooecia in 4 mm^ 14 or 15. 



Occurrence. — Janjukian, Aire Coastal beds, Victoria. 



Holoiype.—V.S.'NM. no. 60205. 



EXOCHELLA JuUien, 1888 

 EXOCHELLA GRANDIS, n. sp. 



Plate 9, fig. 3 



Description. — The zoarium is unilamellar. The zooecia are distinct, 

 separated by a salient thread, large, elongated, hexagonal ; the frontal 

 is a granular pleurocyst, bordered by large areolar pores separated 

 by short costules. The apertura is semielliptical ; the peristome is thin 

 and salient ; a salient rectangular mucron hides the proximal border 

 of the apertura. The ovicell is globular, convex, granular. The avicu- 

 larium is transverse, thin, triangular, acuminated ; it replaces an areolar 

 pore. 



Measurements. — 



r/ja = 0.1 5-0. 1 7 mm . rL.c' = 0.75-0.90 mm 



Apertura^ , ^ „ Zooecia-^ , 



^ 1 /a = 0.1 5 -0.1 7 mm | /.c = 0.50-0.70 mm 



Occurrence. — Balcombian beds at Muddy Creek. Victoria. 



Holotype.— U.S.N. M. no. 8571 1. 



DIDYMOSELLA Canu and Bassler, 1917 

 DIDYMOSELLA CLYPEATA, n. sp. 



Plate 9, figs. 7, 8 



Description. — The zoarium is unilamellar, free ; the fronds are nar- 

 row, bifurcated, formed of about seven longitudinal rows of cells ; 

 the dorsal is covered with an epicalcification hiding the form of the 

 zooecia and on which there are deep longitudinal furrows. The 

 zooecia are little distinct, separated by shallow and inconstant fur- 

 rows, long aliform ; the frontal is convex, formed distally by a shield, 

 and proximally by a tremocyst with large pores. The shield is large, 

 broad, smooth, perf^orated by two large foramina; its distal portion 



