20 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 93 



Family GIGANTOPORIDAE Bassler, 1935 



GIGANTOPORA Ridley, 1881 



GIGANTOPORA HYSTRIX, n. sp. 



Plate 4, fig. 2 



Description. — The zoarium is free, cylindrical. The zooecia are 

 distinct, separated by a large prominent thread, somewhat elongated, 

 hexagonal ; the frontal is convex, pierced by numerous small tremo- 

 pores separated from one another by protruding spinelike granules. 

 Tlie peristomie is long, salient, partly buried on the distal zooecium ; 

 the peristomice is oblique, elliptical, transverse. The spiramen is 

 large (o.i/ mm wide) crescentric, somewhat tubular. The two avicu- 

 laria are small, triangular, almost transverse. 



Measurements. — 



. flip = 0.10 mm . rL-s: = o.85 mm 



Penstomicei ,^ ^ Zooecumi-^ , ^„^ 



] Ip = 0.1 S mm i /.c=:0.75 mm 



Occurrence. — Balcombian beds at Muddy Creek, Victoria. 



Holotype.— U.S.N. M. no. 85728. 



GIGANTOPORA HEXAGONALIS, n. sp. 



Plate 4, fig. 6 



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

 separated by a salient thread, a little elongated, he.vagonal; the frontal 

 is transversely concave, formed by a tremocyst with small pores sepa- 

 rated by regular tuberosities. The peristomice is subcircular ; the 

 peristome is smooth, thin, salient. The spiramen is large (0.14 mm 

 wide), crescentic, bordered by a distinct thread. The two avicularia 

 are large, triangular, oblique, with pivot. The beaks join on the median 

 zooecial axis above the spiramen and form an angle with thickened 

 lines which partially cover the peristomice. 



Measurements. — 



. . flip = 0.20 mm . rL.c = o.90 mm 



Penstomicei ,^ ^ Zooecunn-< , _ ^^ 



I Ip = 0.24 mm I /^=io.55 "''i'''' 



Number of zooecia in 4 mm^ 12. 



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



Flinders, Victoria. 



Holotype.— U.S.N. M. nos. 85725. 85726. 



GIGANTOPORA PERFORATA, n. sp. 



Plate 5, fig. 10 



Description. — The zoarium is free, bilamellar, formed of fronds 

 of varying width. The zooecia are large, little distinct, elongated ; 



