576 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



PLATE 54 



Fig. 1. Rhynchozoon rostratum (Busk), young zooecia Avith details 

 of aperture, suboral avicularium and chamber. 

 The same, old and heavily calcified, with tuberosities. 

 The same, zooecium with ovicell. 



Rhynchozoon tumulosum (Hincks), zooecium with ovicell 

 and suboral and frontal avicularia. 



The same, young zooecium with characteristic bulbous avicu- 

 larium chamber. 



Rhynchozoon tuberculatum Osburn, young zooecium with 

 ovicell and small suboral avicularium. 



Rhynchozoon grandicella Canu and Bassler, young marginal 

 zooecium with suboral and frontal avicularia (both types of 

 avicularia are often larger). 

 The same, young zooecium with ovicell. 

 Rhynchozoon bispinosum (Johnston) operculum. 

 Rhynchozoon spicatum new species, operculum. 

 Rhynchozoon grandicella Canu and Bassler, operculum. 

 Rhynchozoon tumulosum (Hincks), operculum. 



