GENERAL ZOOLOGY 



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Fig. 16.7. Class Ophiuroidea. A brittle star, Ophiopholis aculeala: note the characteristic 

 sharp distinction between the bulbous central disk and the slender, flexible arms. (Photoe;raph 

 by George Lower.) 



Fig. 16.8. Generalized, 



schematic life cycle of an 

 ophiuroid echinoderm. The 

 e;astrula {A) transforms 

 through an indifl^erent pluteus 

 stage into a fully developed 

 ophiopluteus larva (fi), which 

 undergoes metamorphosis in- 

 to a young brittle star. 

 (Adapted from H. B. Fell, 

 1948, Binloaical Reviews, vol. 

 23, printed by permission of 

 the Cambridge University 

 Press.) 



498 



