OPHIURANS OF THE PHILIPPINE AND ADJACENT WATERS. 457 



Fig. 4. Ophiacantha graphica; dorsal surface. 



5. The same; ventral surface. 



6. Ophioplinthaca hastata from station 5280; dorsal surface 



7. Ophioplinthaca hastata from station 5586 ; dorsal surface. 



8. The same ; ventral surface. 



Plate 19. 



Fig. 1. Ophiacantha confusa from station 5240 ; ventral surface. 



2. The same; dorsal surface. 



3. Ophioplinthaca chelys from station 5637 ; dorsal surface. 



4. The same ; ventral surface. 



5. Ophiotreta spatulifera from station 5629 ; ventral surface. 



6. The same ; dorsal surface. 



Plate 20. 

 Ophiotoma assimilis. 



Fig. 1. A specimen from station 5460; dorsal surface. 



2. A specimen from station 5505 ; ventral surface. 



3. A specimen from station 5460 ; ventral surface. 



4. A specimen from station 5450; ventral surface. 



5. The same; dorsal surface. 



6. A specimen from station 5460; dorsal surface. 



7. A specimen from station 5647 ; ventral surface. 



Plate 21. 



Fig. 1. Ophiacantha pentagona from station 5116 ; a portion of the dorsal surface 

 magnified. 



2. Ophiotrenm tertium from station 5349 ; dorsal surface. 



3. The same ; a portion of the dorsal surface, more magnified. 



4. Ophiocopa singidaris from station 5173; dorsal surface. 



5. Ophiocantha pentagona from station 5116; dorsal surface. 



6. The same; ventral surface. 



7. Ophiotrema tertium from station 5349 ; ventral surface. 



8. Ophiocopa singularis from station 5348; ventral surface 



9. The same; dorsal surface. 



Plate 22. 



Fig. 1. Ophiurothamus stultus from station 5660 ; dorsal surface. 



2. The same; ventral surface. 



3. The same ; lateral view of the disk. 



4. The same ; ventral surface of an arm toward its distal extremity. 



5. Ophiurothamnus excavatus from station 5428; lateral view of disk. 



6. The same ; ventral surface of an arm in the distal third. 



7. The same; ventral surface. 



8. The same; dorsal surface. 



9. Ophiomitrella exilis from station 5637 ; ventral surface. 



10. The same; dorsal surface. 



11. Ophiotnyces delata from station 5651 ; ventral surface. 



12. The same ; lateral view. 



Plate 23. 



Fig. 1. Ophioripa marginata from station 4781 ; ventral surface. 



2. The same; dorsal surface. 



3. Ophiothamnus venustua from station 5619; ventral surface. 



