LOWER HELDERBERG ROCKS. 119 



The arm terminates below in a rounded condyle, without any appearance of an 

 articulating surface or point of attachment to any other body; as if the arm, as it 

 now occurs, had had an independent existence; or at least had the power of se- 

 creting calcareous matter to cover the broken and rough extremity, if broken from 

 a body of the usual character of crinoids. This condyle-like extremity of the arms 

 is figured on Plate v, and in a separate fragment represented on Plate vi, fig. 2 & 3. 



PLATE V. 

 Fig. 5. A specimen with the tentacles more closely arranged than usual, and terminating 

 below in a round condyle-like extremity. 



Fig. 6. A specimen preserving eight of the tentacles upon one side of the arm, and four 

 upon the other. 



Fig. 7. An arm coiled, showing the points of attachment, with numerous detached fragments 



of tentacula. 



PLATE VI. 

 Fig. 1. The inner side of an arm with tentacles attached, showing on the right side one at 



unequal distance from the others. 

 Fig. 2 & 2 a. Inner side of the base of an arm including the first three joints, with points 



of attachment for the tentacles t, t ; and the same enlarged. 



Fig. 3. Exterior surface of the same enlarged. 



Fig. 3 a. Transverse section, showing the form of the arm-joints. 



Geological position and locality. In the lower part of the shaly limestone of the 

 Lower Helderberg group ; Helderberg mountains and Schoharie. 



Ci£!\TS EDRIOCRIKIJS ( n- g.). 

 [ Gr. sSfiau, sedeo ; xpivof, lilium.^ 



Body subconicaL Base solid, without division into plates : upper margin 

 marked by six angles, with depressions between for insertion of radial 

 plates. Radial plates five, inserted in the five larger depressions on the 

 upper edge of the calyx. Anal plates two, the lower one inserted in the 

 smaller of the six impressions on the upper margin of the calyx ; the 

 second anal plate placed on the upper edge of the first. Brachial plates 

 numerous, consisting of thin plates in consecutive series resiing upon 

 the upper concave edges of the radial plates : pinnules subdivided 

 above. Tentacula unknown. 



Proboscis unknown. 



Column none. 



