174 EXPEDITION OF THE "ALBATROSS," 1899-1900. 



PLATE 5. 



Fig. 21. Rhopalnnema tyjncum^ HomoBO- 

 nenui ti/picu7}i Maas. 



" 22. Rhopaloiienia typicum. Portion of bell-margiu showing the very mi- 

 nute otocj'sts. 



" 23. Solmissus viarshalli, sp. nov. Side view, natural size. 



" 24. " " Oral view of medusa, natural size. 



" 25. " " View of marginal sense organ. 



PLATE 6. 



Fig. 26. Charybdea grandis, sp. nov. Side view of a young medusa. 



" 27. " " Side view of a tentacle from a mature me- 



dusa, natural size. 



"28. " " Enlarged view of a portion of the flexible 



part of the tentacle, showing the linear 

 arrangement of the nematocysts. 



" 29. " " Enlarged side view of a sense organ of a 



mature medusa. 



" 30. " " Surface view of a sense organ of a young me- 



dusa. 



" 31. " " Enlarged view of one of the velar canals. 



PLATE 7. 



Fig. 32. Nausithoe punctata var. piocifica 

 Agassiz and Mayer. 

 " 33. Nausithoe picta, sp. nov. Oral view of 9 medusa. 



PLATE 8. 

 Fig. 34. Pelagia tahitiana, sp. nov. 

 " 35. " " Oral view of a portion of the disk. 



" 30. Nectophysa WynillrA? Hacokel. 

 " 37. Diphyopsis angustata Haeckel. Terminal nematocyst-battery of a tentacle. 



PLATE 9. 



Fig. 38. Diphyopsis append iculata. Side view of the polygastric generation. 



" 39. " " Side view of the siphosome, showing the order 



of development of the the polypites, tenta- 

 cles, and bracts, (ps) Inferior swimming- 

 bell ; (as) auxiliary swimming-bell. 

 " 40. ErscBa appendiculata. The monogastrie, sexual generation of 



Diphyes appendiculata. 



