RETEOCRINID^. 185 



Xenocrinus Baeri (Meek). 

 Plate IX. Figs. 5a-d. 



1872. Glyptocrinus Baeri — Meek; Amer. Journ. Sci., Yol. III. (3d ser.), p. 260. 



1873. Qlyptocrinus ^«m — Meek; Geol. Rep. Ohio, Palseont., Vol. I., p. 37, Plate 2, Eig. 1. 



1880. Glypiocrims baeri — S. A. Miller; Journ. Cincin. Soc. Nat. Hist., Yol. III., Plate 7, Pig. 4. 



1881, Reteocrinus Baeri — W. and Sf. ; Revision Palseocr., Part II., p. 193. 

 1883. Reteocrinus Baeri — W. and Sp. ; Amer. Journ. Sci., Yol. XXY., p. 266. 



1883, Glyptocrhms baeri — S. A. Miller; Journ. Cincin, Soc. Nat. Hist., Yol. lY,, p. 226. 

 1885. Xenocrinus Baeri — W. and Sp. ; Revision Palseocr., Part III., p. 96. 

 ■ 1889. Xenocrinus baeri — S. A. Miller; North Amer. Geology and Palseont., p. 288. 



Dorsal cup higher than wide ; subovoid ; depressed at the interradial 

 spaces, but not so much so as in X. penicilliis ; cross-section pentangular. 



Basals small, only their upper angles visible in a side view. Radials and 

 costals elongate, formed into conspicuous rounded ridges, which occupy 

 almost the entire width of the plates. Distichals free from the fifth or sixth 

 plate ; the two proximal ones as large as the costals, the third somewhat 

 shorter, and the upper ones but little longer than the free plates. Arms 

 ten, simple, long, rather stout; composed of very short, transverse joints, 

 with slightly convex outer faces. The lower arm joints rectangular, followed 

 by cuneate pieces, which slightly interlock. Interradial areas deepest in the 

 middle ; composed of numerous very small, convex pieces, with a somewhat 

 corrugated surface. Anal side divided by a longitudinal row of anal plates, 

 shaped like the radials and costals. Yentral disk low-hemispherical ; plates 

 very minute; the position of the anus unknown. Column quadrangular, 

 with obtuse angles ; the joints extended outward into long knife-like edges. 



Horizon and Locality. — Hudson River group ; Warren Co., 0., and Rich- 

 mond, Ind. 



The specimens figured are from the Collection of Wachsmuth and 

 Springer, and that of I. H. Harris, Esq., of Waynesville, 0. 



TANAOCRINUS (nov. gen.), W. and Sp. 

 (raT/ao?, slender ; Kptvov, a lily). 



Resembling Reteocrinus, but without infrabasals, and the radials in lateral 

 contact except at anal side. Symmetry decidedly bilateral. Arms long and 

 slender. 



Basals small ; the posterior one truncated at the upper end, and followed 

 by a large anal plate. Costals two, narrower than the radials, and folded 



24 



