572 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



PLATE 52 



Fig. 1. Mucronella labiata (Boeck), zooeciura with ovicell. 



Fig. 2. The same, diagranatic side view. 



Fig. 3. Mucronella <ventricosa (Hassall), zooecium, ovicell and de- 

 tails of aperture. 



Fig. 4. Mucronella major (Hincks), zooecium and ovicell, the com- 

 plete array of spines and the peculiar frontal pores. 



Fig. 5. The same, diagram of side view. 



Fig. 6. Mucronella connectens {RiAXty), zootcmm and ow'ictW. 



Fig. 7. The same, diagram of young marginal zooecium showing 

 details of aperture and the very elongate dietellae. 



Fig. 8. //^wzzVyc/o/iora ^o/z7a (Norman), zooeciura and ovicell. 



Fig. 9. Rhamphostomella cellata (O'Donoghue), with details of ap- 

 erture; note especially the rainute avicularium conforming to 

 the peristomial rim. 



Fig. 10. Rhamphostomella hilaminata (Hincks), zooecium with ovi- 

 cell ; note secondary aperture with high peristomial lappet 

 and elevated avicularium. 



