Paleontology of the Cincinnati Group. 



form ; axial canal pentangular; in other respects agrees with 

 Reteocrinns and Canistocrinus; arms 10 ; column square. (Jour. 

 Cin. Soc. Nat. Hist., Vol. IV, pp. 71, 1876. Wachsmuth & 

 Springer, Revision of Paleocrinoidea, part 3, 1885, p. 95.) 



Remarks. — The above is mainly the description of Wachs- 

 muth & Springer. Two species have been referred to the 

 genus which are given below. 



1.— X. peniciixus S. A. Miller, 1881. 



Basals 4, uniting at the angles of the column, about twice 

 as wide as high, 2 hexagonal, 2 pentagonal, with a granulous 

 surface ; primary radials 3 in each series, about twice as long 

 as wide, each series forming a convex, elevated ridge, con- 

 tracted at point of union of plates ; 4 of the series supported 

 in the angles formed at the junction of the basals, the 5th 

 or posterior series supported on the middle of the basal oppo- 

 site the azygous side; these plates all about the same length; 

 third primary radials a little wider above than the others, and 

 supporting on the 2 superior sides the secondary radials ; 

 secoyidary radials, or brachials continued into the free arms, 

 the first plate about as long as a primary radial and gradually 

 decreasing until the sixth plate is only about one-half as long 

 as wide; above this, plates shorter, but of about the same 

 width until arms are free from vault when they become 

 cuneiform, with the width equal to the length of about 3 

 plates ; iiiterradial and inter-secondary radial spaces long, nar- 

 row and depressed, covered with small plates, each with a 

 short spine or tubercle in the center ; about 75 plates in each 

 interradial area, and 25 or more in each inter-secondary 

 radial area before reaching the top of the cup, the plates con- 

 tinuing over the margin and top (?) of the vault, and also 

 more or less of the long probosis ; azygous area large, covered 

 by a series of 7 plates, each about twice as long as wide ; 

 arms 10, composed of cuneiform plates ; pinnules compara- 

 tively coarse, forming a dense fringe on each side, and com- 

 posed of more than 12 plates; column quadrangular at the 

 head, round (?) below, perforated by a small, round orifice. 

 (Jour. Cin. Soc. Nat. Hist., Vol. IV, 1881, p. 72.) 



Locality. — Warren County, Ohio. 



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