514 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



Genus LEKYTHOPORA MacGillivray, 1882 



The colony is encrusting. The peristomie is free above the ovicell ; 

 the very salient peristome bears only a small avicularium. The 

 apertura bears a wide rimule; the operculum is ornamented with two 

 points of attachment, removed from the border. The ovicell largely 

 opens into the peristomie above the apertura. Interzooecial avicu- 

 laria are present. 



Genotype. — LeTcythopora liystrix MacGillivary, 1882. 



Range. — Miocene. Recent. 



Fig. 212. — Genus Catadysis Canu and Bassler, 1927 



A-I. Catadysis challengeriana Waters, 1888. A. Zoarium, natural size. B. 

 Transversal section. C. Portion of a zoarial surface, X 25. The peristomies are 

 buried in a tremocyst with tubules. D. View of a young peristomice. E. Lower 

 part of the secondary orifice; the tube leading to the avicularium projects into 

 the immersed peristome; this is shown in section in Fig. F. (A-E. After Busk, 

 1884.) F. Section through the peristomial aperture, showing the tube leading 

 to the avicularium, X85. G. Diagramatic section of zoarium, X3. H. Section 

 showing the position of the operculum and the ovicell below the peristome. 

 I. Operculum, X85. (F-I. After Waters, 1888.) 



Genus TURRITIGERA Busk, 1884 



The ovicell opens into the proximal portion of the peristomie. The 

 zooecia are indistinct, arranged on one side of the colony with very 

 thick walls, united to each other by connecting tubes. The apertura 

 buried at the bottom of the peristomie, bears a proximal rimule; the 

 peristome bears small salient avicularia; 18 tentacles. 



Genotype. — Turritigera stellata Busk, 1884. Recent (Southern 



Hemisphere). 



Genus CATADYSIS Canu and Bassler, 1927 



The ovicell is hyperstomial, buried in the interior of the zooecial 

 walls and opening in the inferior part of the peristomie. The zooecia 

 are indistinct; the frontal is striated longitudinally; the walls much 



