Deseription of the Plates. 



Plate I. 

 Fig. 1. Sarsia princeps (Haeckel) x 2. 



2. Margelopsis hartlauhii, nov. sp. x 20. 



3. Mitroeomella fidra, nov. sp. x 8. 



Plate II. 



1. Margells nordgaardii, nov. sp. x 15. 



2. Homoeonema platygonon Maas. x 25. 



3. Homoeonema platygonon. Diagram showing the position 

 of the gonads and sense organs. 



Plate III. 



1. Mitroeomella fiilva. Diagram of a quadrant of the 

 umbrella showing the marginal tentacles, eim, and sense 

 organs. 



2. Mitroeomella fulva. The marginal cirri. 



3. Margelopsis hartlauhii. Lateral view of a compound bulb 

 with two tentacles. 



4. Sarsia princeps. A tentacle, outer view. 



5. Margells norclgaardii. A grdup of tentacles, inner view. 



6. Margells norclgaardii. Diagram showing the position of 

 the gonads on the stomach, aboral view. 



Plate IY. 

 Ptychogastria polaris, Allman. 



1. Diagram showing a longitudinal, perradial, section through 

 the entire medusa. Enlarged about eight times. 



2. Diagram showing a transverse section across the upper 

 part of the stomach. 



