EXPLANATION OF THE PLATES. 187 



magnified, from the Philippine Islands. Fig. 7. Same, 

 from the Feejee Islands. 

 Plate VIII. — Fig. 8. Chlorodesmis comosa, Harv. & Bail. ; a tuft, of 

 the natural size. Fig. 9. A filament, magnified. Fig. 

 10. A portion still more magnified, showing the con- 

 strictions near the axils. 



Plate IX. — Fig. 1. Amphitetras Wilkesii, Bail. & Harv. ; top view. 

 Fig. 2. Oblique view. 



" Fig. 3. Cocconeis rhombifer, Bail. & Harv. ; upper 



valve. Fig. 4. Lower valve. 



" Fig. 5. Cocconeis sulcata, Bail. & Harv. 



" Fig. 6. Aulacodiscus Oregonensis, Bail. & Harv. 



" Fig. 7. Triceratium Wilkesii, Bail. & Harv. ; top 



view. Fig. 8. Chain of three frustrules, moderately 

 magnified. 



" Fig. 9. Arachnodiscus Ehrenbergii, Bail. ; moderately 



magnified, showing two specimens attached to an 

 Alga. Fig. 10. A single disc, much magnified. 



" Fig. 11. Isthmia minima, Bail. & Harv. 



" Fig. 12. Terpsinoe musica, Ehr. ; two frustrules. Fig. 



13. Side view. 



" Fig. 14. Climacospileria moniligera, Ehr. ; front view. 



Fig. 15. Side view. 



" Fig. 16. Dictyocha splendens, Ehr. 



" Fig. 17. Spongiolites Anchor a, Ehr. 



" Fig. 18. Amphitetras favosa, Bail. & Harv. 



" Fig. 19. Triceratium orientale, Bail. & Harv. 



" Fig. 20. Campylodiscus Kutzingii, Bail. & Harv. 



" Fig. 21. Spongiolites Agaricus, Ehr. ; in situ, forming 



globular groups among the meshes of a sponge having 

 pin-shaped spiculse. Figs. 22, 23. Separate speci- 

 mens. 



" Fig. 24. Triceratium concavum, Bail. & Harv.; top 



view. Fig. 25. Edge view. Fig. 26. Side view. 



" Fig. 27. Podocystis Adriatica, Kutz. 



" Fig. 28. Cocconeis Parmula, Bail. & Harv. 



" Fig. 29. Hyalosira punctata, Bail. & Harv. ; single 



