464 



REMARKS ON NEW SPECIES OF CRINOIDEA, 



Ataxiacrinus caponiformis, n. a. 



PL XXVJI, Figs, o, ol, o2, o 3. 



Body flat; discoid below the arms; nearly flat on the dome.* Basal pieces five; five- 

 sided, and united they form a pentagonal piece, the sides of which arc nearly equal; the 

 pentelobate opening into the column from the body notching the base of the pieces of 

 the base. The radial piece on the left of Fig. o 2, Plate XXVII, and on the right of Figs. 

 o and o 1, is much the largest piece in the body; is seven-sided, and about half its length is 

 curved over upon the dome, nearly three times as wide as the distance from the ends of 

 the basals to the base of the free rays, which rest upon it. On both vertical sides of the 

 largest piece is placed one subquadrangular piece, the first of the two irregular rays ; 

 upon these rest the second radial pieces ; that upon the ray (Fig. o, Plate XX VII), is much 

 larger than that upon the opposite irregular ray; it is hexagonal in form, and much like 

 the largest piece, and the largest first radials of the other rays. Both of the second radials 

 in the irregular rays, support, each, one supplementary radial, and the base of one of the 

 free rays. The supplementary radials are placed one upon the left side of the ray (Fig. o, 

 Plate XX VII), and is a larger piece than that upon the left side of the opposite ray. The 

 other two first radials, those on the right (Fig. o 2, Plate XXVII) and the left (Fig. o 1) 

 are nearly of the same size, of similar form to the largest radial ; like that they curve over 

 the upper surface of the dome. All of the upper radials, except one which carries (on our 

 specimen) a small subquadrangular piece of one of the free rays, show openings into the 

 body. This one is crushed upon, and probably conceals it. Both of the supplementary 

 radials carry a small fragment (supposed to be) of ray pieces. They appear to be solid ('?), 

 and not open as in the regular ray pieces. The pieces covering the dome; are small and 

 slightly gibbous, and arranged without any apparent order. No oral opening can be per- 

 ceived. 



The form of the arms, and their arangement, is unknown. 



The column is composed of rather thick disks, placed one upon the other, with a thin, 

 muscular disk between them ; they are all pentelobate. A groove lies between the rounded 

 corners of the pieces, which form the column. The thick pieces of the column between 

 the grooves have a depression in their edges, about half the length of the space between 

 the grooves. 



* Tho specimen is slightly crushed, bending toward each Other the irregular rays; producing, by 

 the crashing, several wrinkles on the dome-cover, and pushing it upward. The remains of the free 

 rays on the irregular rays project upward, producing a figure not unlike a dressed capon. The spe- 

 cies is described as if our specimen had not been distorted. 



