33 



BAEYCRINUS FORMOSUS, n. Sp. 



Plate III, Fig. 6, azygous view of calyx, arms and column. 



Species, as indicated by our specimen, rather below the medium 

 size. Column moderate size, pentagonal and composed of alter- 

 nately thicker and thinner plates. Calyx broadly bowl-shaped, 

 twice as wide as high; plates thick, depressed laterally and at 

 the angles, and swelling in the middle part so as to form broadly 

 rounded radial ridges; surface smooth or very finely granular. 



Basal plates forming a pentagonal disc nearly covered by the 

 column. Subradials the larger and more tumid plates of the body, 

 longer than wide, four hexagonal and one heptagonal. First 

 radials wider than long, deeply sunken at the lateral angles, 

 and each having a broadly rounded radial ridge in the middle; 

 facets for the reception of the second radials concave, each a 

 little more than half the width of the plate, suture gaping; 

 superior lateral angles sharply truncated for the reception of 

 the summit plates. Second radials short, transverse, rounded 

 plates, a little longer in one of the rays than in either of the 

 other three preserved in our specimen. Third radials longer 

 than the second, axillary and supporting upon each upper 

 sloping side heavy, strong arms. 



First azygous plate large, quadrangular, wider than high, 

 resting upon the upper side of the heptagonal subradial and 

 separating two first radials. Second plate smaller than the first, 

 but, in our specimen, it is turned in upon the vault so as not 

 to expose the entire surface. 



Arms ten, two from each ray; short, heavy, rounded exter- 

 nally, and composed of rather long slightly cuneiform plates. 

 Every fourth plate on each side bears an armlet, that is, every 

 second alternate plate on opposite sides bears an armlet. The 

 intervening plates that do not bear armlets are the shorter 

 ones. The armlets are short and stout and bear secondary 

 armlets as in B. spectabilis. 



The general form of the calyx and arms will readily distin- 

 guish this from other described species. 



Found in the Keokuk Group, Washington County, Indiana, 

 and now in the collection of Wm. F. E. Gurley. 



-5 G. 



