PLATE 13. 



Fig. 1. Reconstruct ion of anterior rn.l of Dorynionia acuta, sliowinn; nervous system. Labio- 

 huccal system heavily sluicli'il. 



Fig. 2. Same of posterior end of Slrophomenia seandeus. 

 Fig. o. Same of aiilcrior end of Cliaetoderma ervidita. 

 Fig. 4. Same of posterior end of I'roneonienia liawaiicnsis. 



