120 



HYDEOZOA. 



Eeproductive organs in the course 



of the radiating canals. 



Radiating canals arising from 

 the base of the polypite. 

 Ocelli 



Radiating 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. Thaumantiad^. 



Family 3. JEquoridje. 



Family 4. Eucopidje. 

 Family 5. Tbachynemim. 



Family 6. Geryonidje. 



Family 7. -ZEginid^e. 



The Medusidce were termed by Eschscholtz, 

 Cryptocarpae ; by E. Forbes, Grymnophthalmata ; 

 and by (xegenbaur, Craspedota. These words 

 contrast, respectively, with the names Phanero- 

 carpa3, Steganophthalmata, and Acraspedota ap- 

 plied by the same naturalists to a We section of 



the Lacevnavidce. In this 



family 



na- 



j 



which 



group the 

 Lucernariadce is not usually included, many 

 turalists, from a mistaken view of its organisation 

 referring it to the class Actinozoa, of i 

 Professor Milne Edwards has recently made it a 

 distinct sub-class, under the title of Podactinaria. 



8.^ Order j: Lucernaridre. — In these Lucer- 

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

 frequently about an inch in height, terminating 

 proximally j n a stalk of variable length, and 

 furnished with a hydrorhiza, which, like that of 







