13 



DOLATOCRINUS BELL.ARUGOSUS, n. sp. 



Plate III, Fig. 7, basal view; Fig. S, side view, azygous area 

 on the left; Fig. 9, summit view. 



Species below medium size and elegantly sculptured. Calyx 

 hemispherical, truncated below, and expanding to the free 

 arms. Radial ridges consist of small round ridges crossing 

 the central part of the plates and bearing sharp, elongated 

 nodes in the middle part of each plate. They are not trans 

 verse as in D bellulus. The surface is ornamented with very 

 numerous radiating lines that bear sharp small nodes. There 

 are no central nodes on the interradials. Column round. 

 medium size and bears a Large cinque foil, columnar canal. 



Basal plates form a pentagonal one-fourth wider than 

 the diameter of the column, at the surface, and extend 

 up into the calyx, in the form of a hollow cone, which is 

 tilled with the end of the column. First primary radials wider 

 than long and subequal in size. Second primary radials from 

 one-half wider to twice as wdde as long, quadrangular. Third 

 primary radials expand to the superior lateral angles, larger 

 than the second primary radials, about one half wider than 

 long, pentagonal, axillary, and, in one of the rays, on the left 

 lateral side, and, in the one on the right of the azygous area, 

 bear upon each superior lateral side a single secondary radial, 

 which is axillary and supports upon each upper sloping side 

 two tertiary radials. which gives to each of these rays four 

 arms. In each of the other three rays, the third primary 

 radial bears upon one upper sloping side three secondary 

 radials, and upon the other one secondary radial, which 

 is axillary and supports upon each superior sloping side 

 two tertiary radials. In the ray on the left of the azygous area, 

 it is the proximal side of the third primary radial that bears 

 only secondary radials, while the distal side bears the tertiary 

 radials, which is contrary to the usual structure of crinoids. 

 There are, therefore, three arms in each of three rays. The 

 species has seventeen ambulacra! openings to the vault, all of 

 which are directed upward, though the last tertiary and sec- 

 ondary radials are directed outward so that each radial series 

 extends above the interradial areas. 



The azygous area is like the others excepl slightly wider 

 between the arms. Tin- tirst interradials are the largest plates 

 in the calyx, have nine sides and are broadly truncated above 

 for the second interradials. The second interradials are less 



