TKOOST'S CRINOIDS OF TENNESSEE E. WOOD. 



63 



Family BATOCRINIDiE Bather. 

 Genus BATOCRINUS Cassiday. 



BATOCRINUS GRANDIS Lyon. 



Plate 15, fig. 11. 



Actinocrinites urna Troost, Proc. Amer. Ass. Adv. Sci., II (read 1849), 1850, 



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

 Actinocrinus grandis Lyon, Amer. Journ. Sci., XXVIII, 1859, p. 240. 

 Actinocrinus urna Shumard, Trans. Acad. Sci. St. Louis, II, No. 2, 1866, p. 349 



(catalogue name). 



Actinocrinus wachsmuthi White, Contr. Inv. Pal., No. 8, 1880, p. 162, pi. xl, 

 figs, la, b; 2nd Ann. Rep. Dep. Stat, and Geol. Indiana, 1880, p. 510, pi. 

 vii, fig. 6. 



Batocrinus grandis Wachsmuth and Springer, Rev. Palaeocrinoidea, III, 1885, 

 p. 113; North Amer. Crinoidea Camerata, 1897, p. 381, pi. xxvn, figs, la, b, 

 2a, 6.— Weller, Bull. No. 153, U. S.'Geol. Surv., 1898, p. 127 (catalogue 

 name). 



Troost' s description of this species is as follows: 



This species of Actinocrinites has the elegant form of a vase which is rendered more 

 graceful by the elevation of the pelvic plates which form its base; and the great exten- 

 sion of its superior margin, which is circular and supports a dome-shaped coronal 

 terminated in a proboscis, which completes its beauty. 



The curve of the lower part of the body resembles that of the A. 30 dactylus a as rep- 

 resented by Miller (pi. 1, figs. 1 and 2) but at the height of the scapulars [primaxils] 

 the plates assume a great extension in breadth — this extension continues to the very 

 rim, from the edge of which proceed the 20 [?] fingers [arms] etc. the apertures of which 

 are only visible when a side view is taken. 



The plates of which the body is composed are elevated toward the centre — they have 

 no elevated ridges, those that cover the coronal integument are tumous, polygonal. 

 The whole was covered with a granulated integument part of which is yet attached 

 here and there on the surface. 



Judging from fragments which I have often found it must have grown to three times 

 the size of the one figured. 



Occurs abundantly near White's Creek Spring, where I found numerous fragments 

 of it, but only one entire. 



Observations. — The specimen labeled Actinocrinites urna by Troost 

 corresponds with Batocrinus grandis (Lyon) in the features available 

 for comparison. 



The arms are not sufficiently preserved for the full number to be 

 counted, but the left posterior ray shows six arms and the left antero- 

 lateral ray four, hence if the animal were symmetrical with four in 

 the anterior ray it would have twenty-four arms, the number recorded 

 for Batocrinus grandis. 



Slight differences from B. grandis may be noted in the form of the 

 tubercles on the radials and the size of the base of the proboscis, but 

 these may well be merely individual variations. 



« Actinocrinites triacontadactylus J. S. Miller, A Natural History of the Crinoidea, 

 1821, p. 95, pi. i.— E. W. 



