120 



Cincinnati Society of Natural History. 



a slightly projecting rim; interradial areas depressed, transverse 

 section sub- pent agonal; surface covered with small, semi-regularly 

 arranged granules. Column stout, ornamented with projecting nodose 

 rims. Arms very large, robust, fusiform, over two inches long, and 

 having on either side compressed tentacular. 



Plates : Basal of moderate height, broad at the top, and having a 

 projecting rim at the base, composed of large, closely arranged nodes. 

 First radials large, hexagonal; four sides are of equal length, while the 

 two outer upper margins that support the lower interradial plates, are 

 short. Second radials quadrilateral, twice as broad as high, central 

 portion of the upper side curved upward; between the lateral sides 

 are interposed the lower interradials. Third radials semi-crescent 

 shaped, very wide and narrow, with a central elevated angle. Brach- 

 ials ten, one being placed on each of the opposite upper slopes of the 

 third radials, and meeting at the upper angle, the latter ends rest 

 against the second interradials. First interradials five, long hexas- 

 onal, the}' are placed between the second radials, with the two lower 

 sides resting on the adjoining first radials; and their upper sides par- 

 tially support the lateral sides of the third radials. Second interra- 

 dials ten, two being placed above each first interradial, and in one 

 interradial space two more can be seen superimposed upon these. 

 Column composed of thin joints, with central nodose elevations; basal 

 portion of the arms cylindrical, composed of wedge-shaped plates, that 

 are irregularly placed upon each other, each plate extending but half 

 way through the arm, at about three sixteenths inch above the base 

 a regular double series of alternating joints, that meet in the center 

 of the arm, commence, and are continued as far as known ; these joints 

 have the outer margins rounded, and the margins of juncture beveled 

 to a right angle; on the inner side of the arm the joints are curved 

 away from each other, thus producing a shapely defined groove; the 

 inner angle of each joint bears a laterally compressed tentaculum, of 

 which only one long joint can be observed. 



Calceocrinus radiculus, n.- sp. 



Plate V., figs. 3 and 3a. 



Body compressed, cylindrical; arms three, one dorsal and two lat- 

 eral; dorsal arms rounded above; lateral arms cylindrical, bifurcated; 

 basal plate narrow, triangular; lateral angles sharp; column inserted 

 in the interior angle, where there is a circular depression with strongly 

 projecting margins, forming a socket to receiye the rounded end of the 

 column. Dorsal plate linear, wedge-shaped; dorso-lateral plates pen 



