538 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



PLATE 35 



Robertsonidra oligopus (Robertson), ovicell. 

 Cylindroporella tubulosa (Norman), zooecia, ovicell and 

 high peristome with ascopore. 



Semihasivellia sulcosa Canu and Bassler, portion of branched 

 zoarium. 



Diatosula californica new species, zooecia, aperture, oral 

 and interzooecial avicularia. 



The same in advanced calcification, showing ovicell and oral 

 and frontal avicularia. 



Posterula sarsi (Smitt), zooecium with two oral avicularia 

 (one deeply submerged). 



Hippopleurifera mucronata (Smitt), infertile zooecium show- 

 ing form of aperture and oral spines. 

 The same, operculum showing attachment of muscles. 



