298 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



Family Umbonulidae Canu, 1904 



The frontal is a pleurocyst with strong costules and large areolar 

 pores; the aperture large, suborbicular or subquandrangular, without 

 cardelles or with very small ones. The operculum is simple. The geno- 

 type of Umbonula bears a large suboral avicularian umbo and is without 

 spines. The peristome is low or wanting. The ovicell is large and hyper- 

 stomial or wanting. 



Hastings ( 1949a :526) shows that the genus Hippopleurifera Canu 

 and Bassler is related to Umbonula and states: "The two genera may 

 be referred to one family, Umbonulidae Canu, to be placed near the 

 Petraliidae." 



Genus UMBONULA Hincks, 1880 



Zooecia with the primary orifice suborbicular or subquadrangular, 

 lower margin slightly curved inwards, peristome not elevated, no 

 secondary orifice; a prominent umbo immediately below the mouth, 

 supporting an avicularium (Hincks). Genotype, Cellepora verrucosa 

 Esper, 1790. 



No lyrula, no cardelles, frontal a pleurocyst with large areolae and 

 strong costules ; ovicell hyperstomial, opening widely above the aperture. 



Dr. Anna B. Hastings, of the British Museum, has recently re- 

 studied the specimens in the Museum which were assigned to the species 

 of this genus by the older authors. The genotype, verrucosa Esper, 

 cannot be positively identified with any accepted species, but it is 

 undoubtedly an Umbonula, and "Umbonula ovicellata Hastings may 

 be taken as showing the characters of Cellepora verrucosa Esper, geno- 

 type of Umbonula Hincks" (Hastings, 1949:211). The genus, which 

 in the past has been associated with the Smittinidae, is shown by Hastings 

 to have closer relationships with the Petraliidae. 



Umbonula patens (Smitt), 1867 

 Plate 36, figs. 2-3 



Eschara patens Smitt, 1867:22 and 143. 

 Discopora patens, Nordgaard, 1918:80. 

 Umbonula patens, Hastings, 1944:277. 



Zoarium forming a rough incrustation on shells and stones. Zooecia 

 large, averaging 0.75 mm long by 0.45 mm wide but varying greatly; 

 distinct in younger stages, with a raised line in the separating groove; 

 the frontal ventricose, smooth in the central area, with a row of large 



