57 



plate between the tube for the orifice and the azygous area. 

 Notwithstanding these peculiarities, we have no doubt that we 

 are correct in placing the azygous area between the four 

 armed rays. There are four ovarian apertures between eacli 

 of the rays and two between each of the arms which arrange 

 ment gives to the species forty- four ovarian apertures. 



This is a remarkable and extraordinary species readily dis- 

 tinguished from all others, though at first glance resembling 

 D. vasculam and having the arm formula of D. bellulus, 4+3+3- 

 +3+4, a species with which it agrees in no other respect. It 

 is not abnormal. 



Found by George K. Greene in the Hamilton Group, near 

 Charlestown, Indiana, now T in the collection of Wm. F. E. Gurley. 



Family TAXOCRINIM}. 



FORBESOCRINUS CJ KEEN EI, 11. sp. 



Plate IV, F»g. 25, azygous side view; Fig. 2, basal view, show 

 ing pari of the column broken down. 



Species very large; radial series not elevated beyond the 

 interradial areas; plates flattened or slightly convex; sutures 

 beveled. The plates do not overlap, as is usual in this genus, 

 nor does the column taper as rapidly, below the calyx, as 

 usual. 



Basals within the calyx. Subradials wide and only partly 

 exposed. Primary radials four in each series and from two 

 to four times as wide as long. They are directed at an angle 

 of about 45 degrees, so as to give the lower side of the calyx 

 a broadly rounded outline, that is continued into the tertiary 

 series of plates where the calyx has its greatest diameter. 

 The last primary radial in each series is longer than those 

 below 7 it, pentagonal, axillary, and has rather steep upper 

 sloping sides upon which it supports the secondary radials. 

 There are three secondary radials in each of eight series and 

 two in the other two series. The proximal series on the left 

 of the azygous area has only two secondary radials and the 

 distal series, in the ray, on the right of the azygous area, has 

 only two secondary radials. The secondary radials, though of 

 unequal size, are not much smaller than the primary radials. 



—8 



