PALEONTOLOGY OF IOWA. 611 



FIG. 92. 



tiX3C= 



L_\ 



L\ V( V_ <^^\ 



o Wv9 



^S Q^V 

 '> V^ 



r%^r^s 



44oJA > 



=Q L ^-X 



interradials sustains two narrow plates which lie between the brachial plates of the 

 adjacent rays. 



Geological formation and localities. In the Keokuk limestone : Warsaw, 

 Illinois ; White's Creek springs, Tennessee. 



Actinocrinus lowei ( n. s.). 



PLATE XV. Fio. 5 a, b. 



BODY robust, subturbinate ; the arms proceeding from 

 strong spreading supraradial plates which are sustained la- 

 terally and from above by a series of strong plates, giving 

 a marked pentapetalous outline to the fossil. Basal plates 

 strong, rounded below, and angulate at their junction with 

 the radial plates. First radials large, as long or longer than 

 wide, strong, with angular ridges proceeding to the sides, 

 and angularly tuberculiferous in the centre : a strong ridge 

 jjroceeding from the upper side of the first radials, marks 

 the second and third radials, and diverges with the supra- 

 radials. Second radial plates hexagonal, except adjoining the 



