TROOST 's CRINOIDS OF TENNESSEE E. WOOD. 



53 



the sides are not much elevated. It is externally smooth — the cavity for the column 

 pentagonal. This species having a smooth surface displays remarkably well the form 

 of the plates which compose the cup. This species has likewise the circular pits 

 mentioned in the descriptions of the E. ovalis, and the E. laevis [E. phillipsi]. 



I have dedicated this species to my friend Prof. Goldfuss of Bonn who first took note 

 of this genus. 



Supplementary description. — This is a well characterized little 

 species with a low cup and broad base. The basals are small, about 

 two-thirds of their length being concealed by the column. Radials 

 small, invisible in a side view, about half their length bent abruptly 

 inward to form the basal excavation. The lower half of the radials 

 is also bent at a sharp angle in a longitudinal direction, which gives 

 the distinctly pentangular form to the basal cavity. Plates above 

 the first primibrachs concave, the intersecundibrachs and second 

 inter brachials strongly so, which gives a slightly crenate outline to the 

 upper surface of the calyx. 



Under a lens the surface is seen to be finely granulose. 



Observations. — This species is nearest to Eucalyptocrinus depressus 

 Miller, but differs in the much narrower base, nearly straight sides, 

 and in the character of the basal excavations. In E. depressus this 

 is a broad shallow depression including nearly the whole surface of 

 the large radials, while in E. goldfussi it is small, deep, pentagonal, 

 and includes only the lower half of the radials. The plates of the 

 former are also said to be convex and rugose. 



Formation and locality. — Brownsport limestone. Decatur County, 

 Tennessee. 



Cat. No. 39953, U.S.N.M. 



EUCALYPTOCRINUS NASHVILL/E Troost. 



Plate 15, figs. 7, 8. 



Eucalyptocrinites nashvillse Troost, Proc. Amer. Ass. Adv. Sci., II (read 1849) 



1850, p. 60 (nomen nudum); MSS., 1850. 

 Eucalyptocrinus nashvillx Shumard, Trans. Acad. Sci. St. Louis, II, No. 2, 1866, 



p. 370 (catalogue name). — Wachsmuth and Springer, Rev. Palseocrinoidea, 



III, 1885, p. 128 (catalogue name). — Miller, North Amer. Geol. and Pal., 



1889, p. 244 (catalogue name). 



The description by Troost is as follows: 



It is an elongated cup with a narrow bottom and a deep circular cavity for the 

 insertion of the column. Part of the hexagonal costals [radials] form part of the sides 

 of the cup. 



Observations. — This little species is distinguished by the form of the 

 body and the character of the basal excavation. The aperture of the 

 latter occupies nearly the entire width of the base. The cavity is at 

 first shallow, but near the column it bends abruptly inward, forming 

 a second depression, which is cylindrical and is nearly filled by the 

 column. 



