lO SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 93 



VIBRACELLA Waters, 1891 

 VIBRACELLA PARVULA, n, sp. 



Plate 3, figs. 8, 9 



Description. — The zoariuni is a small truncated, solid cone ; the 

 base is ornamented with numerous radial ribs, dichotomously dividing, 

 each containing one or two rows of large lunularian pores. The 

 zooecia are distinct, separated by their mural rim, small, hexagonal, 

 arranged in radial rows. The mural rim is thin, salient ; the crypto- 

 cyst is concave, shallow, smooth ; the opesium is terminal, semielliptic, 

 little elongated, the proximal border being a little convex with two 

 lateral, shallow, opesiular indentations. The vihracula are large, auri- 

 form, primoserial. 



Measurements. — 



. r/;o = 0.1 0-0. 1 2 mm ,^ . fLc = 0.2 c, mm 

 Upesmm^ , ^ ^^ Zooecunn^ , 



^ [/o = o.io mm 1 /.c = o.25 mm 



Occurrence. — Ualcombian beds at Muddy Creek, N'^ictoria. 



Holotype.—U.^.'N.'M. no. 85904. 



SELENARIA Busk, 1854 

 SELENARIA TRIFOLIATA, n. sp. 



Plate 2, figs. 7, 8 



Description. — The zoarium is orbicular, cupuliform, thick, some- 

 what convex ; the inner face is slightly concave, granular, costulated, 

 with a row of large scattered pores in the middle of the radial ribs. 

 The zooecia are distinct, adjacent through their mural rim, hexagonal, 

 somewhat elongated or transverse. The mural rim is thin, salient ; 

 the cryptocyst is shallow, smooth, slightly concave. The opesium is 

 slightly elongated, trifoliate; the distal portion is elliptical and bor- 

 dered laterally by two triangular, very salient apophyses ; the opesiular 

 portion is linear, transverse, with two deep and rounded lateral in- 

 dentations. The vihracula are primoserial, very large, auriform, sepa- 

 rated into two parts by a salient point. The ancestrula is large and 

 surrounded by 10 much smaller zooecia, of which 5 are vihracula. 



Measii rements. — 



. r/jo = 0.27-0.30 mm Zooecia rL^ = 0.40-0. so mm 

 Opesium^ , ^ ^, r -ixS, 



^ 1^/0 = 0.24 mm (margmal)l /xr = o.50 mm 



Occurrence. — Balcombian beds at Muddy Creek, Victoria. 



Cotypes.—U.S.^.U. no. 85863. 



