346 THE CRIXOIUEA CAMERATA OF NORTH AilERICA. 



Eucalyptocrinus inconspectus Rixguebekg. 



Plate LXXXIIL Figs. 1 and 2. 



ISSl. RiNGUEBEEG ; Proceed. Acad. Nat. Sci. Pliila., p. 148, Plate 3, Fig. 5. 



Of rather large size. Borstal cup deep, occupying almost one half of the 

 length of the crown ; semi-ovoid, the sides decidedly convex, rising gradu- 

 ally to the middle of the second costals, thence almost vertically to the top, 

 so that the plates at the upper end are parallel to those of the opposite side. 

 Plates flat — the general curvature excepted — and without ornamentation 

 or other markings,* the suture lines indistinct. 



Basal concavity narrow and filled completely by the upper part of the 

 column. Radials about as long as their width near the top, rapidly tapering 

 downward, the extreme lower end gently curving inward and taking part in 

 the columnar concavity; the sloping upper faces very short. First costals 

 as wide as long, a little narrower at the upper end, the sides slightly convex. 

 Second costals as long as the first, widest at two thirds their height, some- 

 times the upper angle slightly touched by the interdistichals. First distichals 

 a third smaller than the upper costal, the second very small, and the suc- 

 ceeding palmars still smaller and irregularly pentangular. First interbrachial 

 extremely large, decagonal, about a third longer than wide, attenuate at 

 both ends ; the two of the second row shorter, and together narrower than 

 the first, their upper and lower ends forming re-entering angles. The 

 interdistichal approaching the two upper interbrachials in form, but con- 

 siderably smaller; its upper end squarely truncated, and rising to the third 

 arm plate. Partition walls narrower than the arms, and of uniform width 

 throughout ; their outer edges flat at the proximal, and convex at the distal 

 end. Arms gradually tapering, rounded exteriorly ; the three lower joints 

 single, and a little longer than the upper, which are extremely short. Struc- 

 ture of disk and summit unknown. 



Horizon and Localit//. — In the white limestone at the upper part of the 

 Niagara group ; Rochester, N. Y. 



Bemarlcs. — Nearest to E. crassv-t, but the sides of the dorsal cup dis- 

 tinctly rounded, the base not truncated, and the basal concavity very much 

 smaller. 



* Hini'ncbcrg described tlic surface as "finely rugose; ruga; giving evidence of irregular radiations 

 from tlic. larger plates." We liave carefully examined liis type, but cannot discover any ornamentation; the 

 roughness upon the surface is evidently caused by wcalhciiug. 



