37 



Brachials about the same size and form as the radials, and sup- 

 port an their upper sloping sides the first arm plates. Arms two to 

 each ray, composed of quadrangular joints that gradually diminish 

 in width to their extremities. 



Anals, three visible ; the first is nearly as large as the radial 

 plates, pentagonal and situated as in Poteriocrinus, between two of 

 the subradials, and partly under the left side of the right posterior 

 radial. The second is about half as large as the first, and rests on 

 the upper truncated margin of the left posterior subradial. The 

 third is very small, and rests upon the upper angle of the first anal. 



Position and locality: Chester limestone, Monroe county. 111. 



Illinois State collection. 



AGASSIZOCKINUS HEMISPHERICUS. N. SP. 



Body small, bowl- shaped or hemispherical in outline, about once 

 and a half as wide as high to the summit of the radial series, round- 

 ed at the base, and composed of massive protuberant plates. 



Basals small, projecting but slightly below the subradials, form- 

 ing a little pentagonal star. Ko columnar facet is visible. 



Subradials a little longer than wide, strongly protuberant, three 

 of them pentagonal, and two on the posterior side hexagonal. 



Eadials pentagonal, three of them rather more than once and a 

 half as wide as long, the two on the posterior side rather narrower 

 than the others, and all truncated squarely across their summits for 

 the reception of the brachials. Sutures between all the plates of 

 the body distinct. 



Brachials as wide below as the radials, but strongly constricted 

 and sharply angular above, where they give support to the two divi- 

 sions of the rays. The arm plates attached are three in number, 

 the first nearly twice as long as the succeeding ones, and all quad- 

 rangular in form. 



Four anal plates are visible, the first is protuberant, pentangular, 

 about half as large as the largest radials, and rests squarely upon 

 the truncated upper margin of the right posterior subradial, and 

 under the left side of the right posterior radial. 



The second anal is about half as large as the first, longer than 

 wide, and rests- on the upper margin of the left subradial. The other 

 anals are smaller, the third rests between the first and second, and 

 the fourth on the summit of the second. 



Column unknown. 



Position and locality : Chester limestone, Eandolph county. 111. 



Illinois State collection. 



LECYTHIOCRINUS ADAMSI. N. SP. 



Body of medium size, irregularly subovoid, slightly pentalobate, 

 as seen from above or below, from the protuberance of the radial 

 plates, and composed of smooth and rather thin plates. The base is 

 convex, and occupies about one-fourth the entire length of the body. 



