60 



arms in the species, and thai the two arm furrows unite within 

 the axillary, second radial, so as to connect with the interior 

 of the calyx, through the single notch or arm furrow in the first 

 radial. A rather long, convex, azygous plate truncates a sub- 

 radial and extends as high as the top of the first radials, where 

 it is followed by two convex plates of ab6ut equal size, that 

 articulated with the other plates. 



This species differs so from other species of JEsiocrinus that 

 it is with some hesitation we refer it to that genus, though the 

 general structure of the calyx, aside from the sculpturing of the 

 plates and sunken sutures, agrees more nearly with that genus 

 than with any other that has been defined. 



Found in the Upper Coal Measures, at Kansas City, Missouri 

 and now in the collection of Wm. F. E. Gurley. 



EUPACHYCRINUS PARVUS, n. Sp. 



Plate VI, Fig. 22, basal view of calyx; Fig. 23, azygous side 



view. 



This is the smallest known species, in this genus, and differs, 

 in every particular, from all of them, except in the number and 

 relative position of the plates of the calyx. Calyx very low, 

 more than twice as wide as high; subpentagonal in outline, 

 columnar cavity embracing the basals and nearly half of the 

 subradials; sutures distinct and sunken at the angles; surface 

 smooth. 



Basal plates about one-half wider than the diameter of the 

 column; citatrix for the columnar attachment concave, radi- 

 ately furrowed, and pierced by a very small pentagonal colum- 

 nar canal. Subradials the larger plates of the calyx, though 

 not of uniform size, the one on the right of the azygous side 

 being the larger. They abruptly bend down into the columnar 

 cavity, where each bears one or two concave furrows as if 

 gouged out with a small circular chisel, and abruptly curve up- 

 ward and reach nearly to the top of the calyx. They are con- 

 vex, externally, and the sutures are depressed, the depression 

 being most marked at the angles. First radials twice as wide 

 as high, pentagonal, the lower angle extending nearly to the 

 bottom of the calyx, truncated the entire width above, and 

 much thickened within; sutures gaping, but immediately within, 



