456 BULLETIN 100, UNITED STATES NATIONAL, MUSEUM. 



PLATE 13. 



Ophiotreta matura. 



FIG. 1. A specimen from station 5506 ; ventral surface. 



2. A specimen from station 5526 ; dorsal surface. 



3. A specimen from station 5339; ventral surface. 



4. A specimen from station 5467; ventral surface. 

 5 : A specimen from station 5499 ; ventral surface. 



PLATE 14. 

 Ophiotreta matura. 



FIG. 1. A specimen from station 5424 ; dorsal surface. 



2. The same; ventral surface. 



3. A specimen from station 5538 ; ventral surface of an arm. 



4. A specimen from station 5511 ; dorsal surface. 



5. The same ; ventral surface. 



PLATE 15. 



FIG. 1. Ophiotreta matura from station 5648; a portion of the dorsal surface 



of the disk. 



2. Ophiotreta matura from station 5424; a portion of the dorsal surface 

 of the disk. 



3. Ophiotreta matura; a portion of the ventral surface of an arm. 



4. Ophiacantha vorax from station 5606 ; dorsal surface. 



5. The same; ventral surface. 



6. Ophialcaea congesta from station 5219 ; ventral surface. 



7. The same; dorsal surface. 



PLATE 16. 



. 



FIG. 1. Ophiacantha dollasii from station 5399; dorsal surface. 



2. The same; ventral surface. 



3. Ophiacantha dollasii from station 5135 ; ventral surface. 



4. Ophiotreta valenciennesi from station 5306; dorsal surface of an 



arm. 



5. Ophiacantha henigna from station 5592; ventral surface 



6. The same ; dorsal surface. 



7. Ophiacantha duplex from station 5348; dorsal surface 



8. The same; ventral surface. 



PLATE 17. 



8 



2. The same ; ventral surface. 



FIG. 1. Ophiacantha severa from station 5629; dorsal surface. 



3. Ophiacantha severa from station 5645 ; dorsal surface. 



4. Ophiacantha legata from station 5536; dorsal surface. 



5. The same; ventral surface. 



6. Ophiacantha longidens from station 5153 ; ventral surface. 



7. The same ; dorsal surface. 



r 



PLATE 18. 



FIG. 1. Ophiacantha pacata from station 5589 ; dorsal surface. 



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



3. The same; ventral surface. 



