1. Actinotrocha from Messina, Mediterranean, type of larva 

 of PJioronis hippocreina, 2. Actinotrocha hrancliiata from St. 

 Andrews, larva of Plioronis ovalis. 3. Actinotrocha from Ceylon, 

 type of larva of Plioronis hiiskii. 4. Actinotrocha, after Wilson, 

 larva of Plioronis architect a. 



