dTAGZ "D" . CO HOURS. 

 The chare:- which have taken place in "C" to 

 produce "D" ar2 very narked. 



The cilia have disappeared except in four trans- 

 verse rings, three ef which axtend entirely around 



of the larva. The third ring, counting from 

 the anterior end, is interrupted by the mout -fr — &«d 

 oral disk on the ventral surface. 



This third ciliated ring first appears or. V. : 

 lateral bulges which were described in "C",and the 

 fourth ring appears on a second pair of lateral bul- 

 ges which originate behind the first pair near t 

 posterior end of the larva*.. 



The shape o2 the larva. -is no longer oval but 

 the posterior end has widened latterally and become 

 somewhat dorso-ve-ntrally compressed. Fig ,0. The anter- 

 ior end has not changed in shape and may be spoken 

 of as forming the handle of the club shaped larva. 



Tile enlarged posterior end of the larva contains 

 all its organs and is the part which will enter di- 

 rectly into the formation of the adult ophiurid. 

 From its homology with the preoral lobe and 

 larval organ of Asterjna gibbosa i have called the 

 anterior end of the larva the larval organ. It dio- 



