FIG. 9. THE STARFISH, Asterias. 



at. Normal gastrula ; may be bisected along the main axis or at right angles to it (see 



dotted lines). 



a 2 . Normal larva, " Bipinnaria." 

 fci. Small but whole gastrula that results by a process of regulation from the parts of a 



bisected gastrula. 

 fc 2 . Small but whole " Bipinnaria," developed out of b 1 . 



