128 PALEONTOLOGY OF OHIO. 



Genus EUCALYPTOCRINUS, Golclf. 



EUCALYPTOCRINUS SPLENDIDUS, TrOOSt. 



Plate 6, fig. 12. 



Eucalyptocrinus splerididus, Troost ; Proc. Am. Assoc. Adv. Sci., 1848, p. 60. 



Calyx low and spreading, cyathiform, or nearly hemispherical, about 

 twice as wide as high, measuring to the base of the arms ; sides some- 

 what regularly rounded; base slightly impressed for the reception of the 

 column. Above the calyx the edges or backs of the interbrachial plates 

 are nearly vertical, giving a breadth just below the top of these plates 

 but little less than that at the summit of the calyx. Oral (?) aperture, at 

 the center of the summit of the interbrachial plates, broad funnel-form, 

 communicating with the cavity of the body by means of a long, rather 

 large, canal. Basal plates of the calyx very small, concealed within the 

 cavity of the column ; first radial plates forming the base of the cup and 

 reaching but a short distance up the sides; second raclials quadrangular, 

 a very little wider than high; third radials pentangular, with the apex 

 truncated by the smaller interbrachial plates, and supporting on the lat- 

 eral faces the smaller pentangular supraradials, which in turn support 

 the plates on which the free arms rest, two to each division, or four to 

 each ray. Interradial plates large, higher than wide, broadest above the 

 center, supporting two elongate intersupraradials, which in turn support 

 the larger interbrachial plates. Arms unknown, from Ohio specimens. 



The specimen from which the description is taken is, so far as we are 

 aware, the first example of the species recognized, aside from the original 

 specimen in Dr. Troost's collection. It is an internal cast, preserving 

 the filling of the internal cavity of the body, the impressions of two of 

 the interbrachial plates, and the filling of the central canal leading from 

 the summit aperture to the interior of the body, the upper portion of the 

 specimen having been split vertically through the center. It shows the 

 form of the internal cavity, and the form and size of the canal leading 

 from it to the summit or oral aperture, and forms on the whole a very in- 

 teresting specimen. 



The species is chiefly distinguished from others of the genus by the 

 vertical line of the back, or outer face, of the interbrachial plates, those 

 on the opposite sides of the body being parallel with each other. 

 All other species known from rocks of the same age in this country 

 are more or less contracted, or inclined inward toward the top, giving 



