33 



and supports the third, which is three times as wide as high, 

 pentagonal, axillary, and supports upon the upper sloping sides 

 the secondary radials. 



In one of the secondary radial series there are three plates, in 

 six of them each has four plates, in two of them each has six 

 plates, and one of them has five plates. One ray which is opposite 

 the azygous area, having six secondary radials, supports upon 

 each upper sloping side tertiary radials, which continue to the 

 end of the arms. Nine other tertiary radial series do not bifur- 

 cate, but so far as can be determined all the others bifurcate 

 once, and one of the arms thus thrown off in each series bifurcates 

 again, except in one ray. This gives us eight arms in each of 

 four series, but only five arms in the ray opposite the azygous 

 side, which possesses three primary radials, thus making thirty- 

 seven arms in this species. But there is some injury to the 

 specimen in two or three places, and the last bifurcation may not 

 take place in one or two rays, and possibly, therefore, the species 

 may have only thirty- six arms. 



The azygous area commences with one plate, sending a sharp 

 angle between the first radials to the angle of a subradial; this is 

 succeeded by three plates in the second range, and these by three 

 plates, and these again by two, the superior plate being the 

 largest in the area and acutely pointed above. There are, there- 

 fore, nine azygous plates. 



Found in the Kaskaskia Group, at Bowling Green, Kentucky, 

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



poteeiocrinus scopae, Miller & Gurley. 



Plate III, Fig. 1, lateral view magnified two diameters; Fig. 2, 

 lateral view of same specimen natural size, 

 azygous area on the left. 



When the authors described this species in 1890 in their "De- 

 scription of some new genera and species of Echinodermata from 

 the Coal Measures and Subcarboniferous Bocks of Indiana, Mis- 

 souri and Iowa," which work was subsequently reprinted in the 

 17th Report of the Geological Survey of Indiana, only the azygous 

 side was illustrated, and, as it seemed desirable to have it further 

 illustrated, two lateral views are here presented, one natural size 

 and one magnified two diameters. 



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