120 



HTDRQZOA. 



Eeproductire organs in the course 

 of the radiating canals. 

 Kadiating canals arising from 

 the base of the polypite. 



Ocelli 



Eadiating canals arising from 

 the outer margin of the poly- 

 pite. Vesicles. . 

 Reproductive organs as rounded 

 protuberances of the radiating 

 canals. Vesicles. 

 Tentacles contractile. . 

 Tentacles stiff. 

 Reproductive organs as flattened 

 expansions of the radiating 

 canals. Vesicles. . 

 With pouch-shaped prolongations 

 of the polypite, in which the re- 

 productive products are formed, 

 Vesicles 



Family 2. Thaumantiada 



Family 3. JEquoridjjj. 



Family 4. 

 Family 5. 



EucopiD^. 



TuACHYNEMIDiE. 



Family 6. Gebyonid^. 



Family 7. JEaimDM,. 



The Medusidce were termed by Eschscholtz, 

 Cryptocarpge ; by E. Forbes, G^ymnophthalmata ; 

 and by Gegenbaur, Craspedota. These words 

 contrast, respectively, with the names Phanero- 

 carpae, Steganophthalmata, and Acraspeda ap- 

 plied by the same naturalists to a large section of 

 the Lucernai'idce, In this group the family 

 Lucernariadce is not usually included, many na- 

 turalists, from a mistaken view of its organisation, 

 referring it to the class Actinozoa, of which 

 Professor Milne Edwards has recently made it a 

 distinct sub-class, under the title of Podactinaria. 



8. Order J: l<iieernaridsp. — In these Lucer- 

 nariadce the body is more or less cup-shaped, and 

 frequently about an inch in height, terminating 

 proximally in a stalk of variable length, and 

 furnished with a hydrorhiza, which, like that of 



