io 4 



MANUAL OF ZOOLOGY 



SECT. 



subject to considerable variation. The gonads are some- 

 times, as in Obelia, developed in the radial canals, some- 



FIG. 46. Bougainvillea ramosa. A, entire colony, natural size. B, portion of the 

 same magnified ; C, immature medusa ; dr. c. circular canal ; cu. cuticle or 

 perisarc ; ent. cav. enteric cavity ; hyd. polype or hydranth ; hyp, hypostome or 

 manubrium ; med. medusa ; mnb. manubrium ; rod. c. radial canal ; t, tentacle ; 

 v- velum. (From Parker's Biology, after Allman.) 



