540 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



PLATE 36 



Hippopleurifera mucronata (Smitt), ovicell and aperture. 



Umhonula patens (Smitt), infertile zooeciura. 



The same, ovicell. 



Umhonula alvareziana (d'Orbigny), zooecium, aperture and 



avicularia. 



The same, operculum. 



Umhonula arctica (Sars), zooecium with paired oral avicu- 

 laria. 



Rag'tonula rosacea (Busk), zooecium, aperture, avicularium. 



Lacerna fistulata (O'Donoghue), zooecium with ovicell in 



complete calcification. 

 Fig. 9. The same, at a younger stage, with ovicell and fistula-like 



avicularian umbo. 

 Fig. 10. The same, young zooecium with low umbo and avicularium. 

 Fig. 11. The same, operculum, enlarged. 



