CLASS OF THE ECHINODEBMATA. 529 



which resemble small balloons ; the cestidse, which have the 

 form of a long gelatinous ribbon ; and the phj'sophoridse, 

 which have the appearance of a garland of flowers and 

 fruits * 



The medusa produce eggs like most animated beings, but 

 the young which spring from, these in no shape resemble the 

 mother; they are small ovoid bodies, having their surface 

 provided with vibratile cilia, and which soon are fixed, and 



Fig. 555. Sea Blubber (Medusa Pelagica) ; 

 JeUy Fish. 



as they become developed form zoophytes, already known to 

 naturalists by the name of hydroid polypi (sertularidse, for 

 example) ; these multiply by granulations, so as to constitute 

 colonies of aggregated animals ; and the different individuals 

 of the new generation thus produced become free as the} T are 



* In this family, including the physalidse, the body is floated by air cells, 

 and locomotion performed by parts exposed to the wind. R. K. 

 M M 



