EXPLANATION OF PLATE L 



ACERVULARIA ADJUNCTIVA. 



Fig. 1, a small cluster of corallites, natural size. Fig. 2, transverse section of ibe 

 aame. Fig. 3, vertical section of a single corallite. 



LECYTUIOCRINUS OLLICUL^FORMIS. 



Fig. 4, side view of body enlarged to 1^ diameters. Fig. 5, diagram of the same, in 

 the same proportions. 



ERISOCRINUS PLANUS. 



Fig. 6, basal view of body, natural size. Fig. 7, view of oval side of the same. 

 I ig. 8, similar view of the Poteriooinus hemisphericus Shumard, for comparison. 



CYATIIOCRIXUS STILI.ATIVUS. 



Fig. 9, side view of calyx, natural size. Fig. 10, basal view of the same. 



RHODOCRINUS VESPERALIS. 



Fig. 11, side view of the body, natural .size. Fig. 12, basal view of the same. 



ARCII^OCIDARIS DININNU. 



Figs. 13, 14, and 15, views of different spiaes. 



