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Fig. 128. — Development and metamorphosis of the starfish. A, Dorsal view of 

 early ciliated larva showing ciliated bands, and left and right coelomic pouches. 

 B, Ventral view of bipinnaria larva showing the extension of the left and right 

 coelomic pouches. C, Dorsal view of the same larva showing the left madreponc 

 pore and water tube, and the fusion of the left and right coelomic pouches to form 

 an anterior coelom. D, Dorsal view of an older larva showing the budding of the 

 five water tubes from the left coelom. E, Left side view of a still older larva show- 

 ing the water vascular system developing from the water tubes, and the rays of 

 the adult starfish developing on the dorsal side. F, Brachiolaria larva in process of 

 metamorphosis. The larva has settled on the preoral region which is greatly short- 

 ened. Q, Aboral view of a young starfish showing the developing spines. 



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