570 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



PLATE 51 



Rhamphostomella spinigera Lorenz, zooecia and ovicell with 

 details of aperture, avicularia and spines. 

 Rhamphostomella toivnsendi new species, young zooecium, 

 with details of aperture and frontal decoration. 

 The same, ovicell and avicularium. 



Cystisella saccata (Busk), zooecium with incomplete ovicell. 

 The same, ovicell. 



Cystisella bicornis new species, with ovicell, spinous proc- 

 esses and avicularium. 



The same, front of avicularian chamber removed to show 

 its mode of origin. 



Parasmttt'tna calif ornica (Robertson), young zooecium show- 

 ing aperture and mode of growth of the pleurocyst. 

 The same, ovicell. 



The same, with numerous avicularia. 

 The same, giant avicularium. 



