8 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.65. 



Figs. 6, 6a. Side and terminal views of a stem-fragment altered somewhat 

 like the last, but in which the radial structure.s have been destroyed by 

 chemical action, leaving the more substantial petal sectors strongly outlined, 

 but without trace of crenellae. 



Fig. 7. A stem with smooth, unaltered sides, except near the upper end, where 

 there is the remnant of a cirrus-facet. 



Fig. 8. A smooth stem with probably a nodal columnal at each end. Two 

 cirrus-facets are clearly shown at the upper face, at adjoining radii. 



Figs. 9, 9a. Two views of an unaltered stem-fragment, with the epizygal at 

 the top (so posed in photographing for better lighting of the structures), 

 showing 3 cirrus-facets well preserved, oblique to the general surface, two 

 at adjoining radii, and the third one opposite, leaving the two intervening 

 radii blank. The peripheral crenellae are distinct in some parts of this face, 

 but no trace of radii can be seen upon it. 



Figs. 10, 10a. Two views of a fragment consisting of two columnals, on one 

 of which the normal joint-face is in good condition. The petal floors are 

 depressed, as usual in the genus, the radial ridges slightly elevated between 

 them, indented with faint narrow canals leading to the radial center; the 

 peripheral crenellae are distinct, 10 or 12 in number to the sector, with the 

 outer pair next to the radii slightly receding from the margin. 



