PLATE XII. 



Phormosoma placenta Wyv. Thoms. 



Fig. I. Seen in profile, natural size. 



from tli.- abactinal side. 



Fig. 3. Same seen from the actinal side. 



Fig. 4. Portion of actinal system denuded, magnified. 



Fig. 5. Coronal plates of the abactinal side, near the ambitus, magnified. 



Fig. 6. Edge of test, shofl big the ambital fasciole from tli>' abactinal side, magnified. 



Fig. 7. Portion of test, facing the ambital fasciole, magnified. 



Fig. 8. One of i in club shaped spines of the actinal surface, magnified. 



Fig. !). Denuded abactinal system, somewhat magnified. 



