486 



CCELENTERA TES. 



resemblance to the tube-feet of the star-fishes, being very elastic and contractile, 

 and carrying a sucker at the tip. They are used in the living state for attachment, 

 and for creeping in the manner of a star-fish. The disc of Pectis is about H 

 inches in diameter. 



Of the forms among which the reproductive individuals swim away as jelly- 

 fish, we may take as an example Corymorpha nutans. In this creature, between 

 the five individuals grouped together in the illustration, five small creatures, each 

 provided with a filamentous appendage, are to be seen swimming, which are the 

 medusae belonging to this animal. Each egg of these minute medusas, which are 

 no larger than in the illustration, develops into a ciliated larva, which, sinking to 



Corymorpha, WITH DETACHED MEDUSAE. 



the bottom, grows into an attached Corymorpha. The illustration shows these 

 animals, which in the polyp form are always single, of the natural size. Unlike 

 most animals of this sort, they do not attach themselves to seaweed or stones, but 

 live on fine sand, into which they sink the posterior end of the stem. Numerous 

 thread-like appendages of this buried part penetrate the sand in all directions, 

 thus firmly attaching the animal. The mouth at the anterior end is encircled by 

 tentacles, a second circle of tentacles surrounding the widened part of the body 

 which contains the stomach. Immediately above this latter circle, the buds stand 

 in clusters; in summer they are found in all stages of development, and even 

 while attached to their stalks assume the complete structure of a medusa. They 

 move their umbrellas actively, break loose, and thus complete the circle of develop- 



