4:58 



RADIATA : ACALEPH.E. 



FIG. 689. 



SUB-SECTION II. 

 THE OEDER OF CTENOPHOR^ OR BEROID MEDUSAE. 



THE Beroid Medusas are more or less spherical, or 

 melon-shaped, with eight rows of locomotive fringes di- 

 viding the surface of the body 

 as the ribs divide the surface of 

 a melon. 



Pleurobrachia is one of the 

 most common kinds on the north- 

 east coast of the United States, 

 and in its movements and curi- 

 ous appendages is one of the 

 most wonderful of all the Me- 

 dusse. It is transparent, and 

 besides the eight rows of fringes, 

 it has two most extraordinary 

 tentacles ; and no form of ex- 

 pansion or contraction, or curve, 

 or spiral, can be conceived of 

 which these tentacles do not as- 

 sume. 



Bolina and Idyia are other 

 ctenophorse common on the 

 north-east coast of the United 

 States. The Rose-colored Idyia 

 is three or four inches long, and 

 rteuroi>racMarhociodactyia,Ag& sa i Z . shaped somewhat like a melon 



with one end cut off; and the 



mouth occupies the whole of the cut-off end, and the 

 digestive cavity, or stomach, occupies a large part of the 



