PLATE 20. 



Figs. I, 2, and 3. Proboscidactyla ornata, young medusae. Agassiz Labora- 

 tory, Newport, Rhode Island, June, 1892. 

 Fig. 4. Proboscidactyla ornata, young medusa with tentacles expanded. 



Agassiz Laboratory, Newport, Rhode Island, July 3, 1893. 

 Fig. 5. Part of a tentacle of the medusa shown in figure 4. 

 Fig. 6. Proboscidactyla ornata, young medusa having 8 terminal branches 



to the radial-canals. Agassiz Laboratory, Newport, Rhode Island, 



July, 1892. 

 Figs. 7 and 8. Proboscidactyla ornata, young medusae showing variations in 



color. Agassiz Laboratory, Newport, Rhode Island, July 26, 



1895. 

 Fig. 9. Proboscidactyla ornata, mature female in which the radial-canals 



have 12 terminal branches. Agassiz Laboratory, Newport, Rhode 



Island, September 17, 1896. 

 Fig. IO. Proboscidactyla ornata. Oral view of a mature female in which the 



radial-canals have 16 terminal branches. Agassiz Laboratory, 



Newport, Rhode Island, September 12, 1892. 

 Fig. II. Rathkca octofiunctata. Half-grown budding medusa. Abundant 



among masses of floating ice in the harbor. Woods Hole, 



Massachusetts, March 4, 1907. 



See page 178 for description of figure 11. 

 Drawn from life, by the author. 



