TAXOCRINIDAE 367 



Type. The specimens considered as types, being those of figures 1, 2, 3, and 7, are in the 

 author's collection. The original of figure 5 is in the collection presented to the University 

 of Toronto by Sir Edmund Walker ; that of figure 6 is in the American Museum of Natural 

 History, New York; and that of figure 4 in the U. S. National Museum. 



Horizon and locality. Middle Devonian, Hamilton group ; Thedford, Ontario, Canada. 



Eutaxocrinus gracilis (Meek and Worthen) 

 Plate XLIX, figs. S, 8b 



Taxocrinus gracilis Meek and Worthen, Proc. Acad. Nat. Sci. Philadelphia, 1865, p. 142; Geol. Surv. 



Illinois, III, 1868, p. 421 with text-fig., pi. 13, fig. 3. — Wachsmuth and Springer, Revision Palaeocri- 



noidea, pt. 1, 1879, p. 48. 

 Rhodocrinus (Taxocrinus) gracilis, Shumard, Trans. Acad. Sci. St. Louis, II, 1866, p. 397. 

 Not Taxocrinus gracilis Schultze, Mon. Echinodermen Eifler Kalkes, p. 37, pi. 4, figs. 3, 3a. 



This species was described from an abnormal specimen in which the structures are so 

 distorted that specific characters are not to be defined. It belongs to this genus, and has a 

 habitus somewhat like that of E. ivhiteavesi, but the brachial arrangement is much more 

 delicate, and it has small interbrachial plates. Three rays are abnormal, but the other two 

 have 3 IIBr, and that is probably its normal number. It would thus find a place in the list 

 just preceding E. fletcheri. It is probably a good species representing the genus in the 

 western Hamilton. I give two figures of the type and only known specimen. Some other 

 specimens probably of this genus have been found in the Hamilton of Iowa and Illinois, but 

 not in good enough condition for description. 



Type. University of Illinois. 



Horizon and locality. Middle Devonian, Hamilton group ; Jackson County, Illinois. 



Eutaxocrinus ithacensis (Williams) 

 Plate L, figs, i, J 



Taxocrinus ithacensis Williams, Proc. Acad. Nat. Sci. Philadelphia, 1882, p. 28, pi. 1, fig. 10. — Wachsmuth 

 and Springer, Revision Palaeocrinoidea, pt. 3, 1886, p. 144. — Kindle, Bull. Amer. Palaeontology, II, 

 1896, p. 33- 



A small species. Crown elongate, turbinate, narrowly expanding to IIIBr, 

 where height to width is 1.2 to 1. Calyx narrow, with small base; side outline 

 straight, spreading to top of I Ax, 1 to 2.6; height to width, i to 1.2. Arms 

 broadly rounded, tapering rapidly to small ends. Rays with smooth margins, 

 increasing in width from RR up leaving only narrow, elongate spaces. No iBr. 

 Surface smooth. 



IBB low, like a columnal. BB small. IBr increasing in width upward. 

 IIBr 3 or 4, the latter number predominating; two more bifurcations beyond, 

 after which the arms infold. Column large and long, enlarging at the calyx 

 where it is flush with the basal ring, and also toward the root ; proximal columnals 

 very thin, strongly crenulated, narrowing for about 5 mm., beyond which alter- 

 nate columnals increase in length somewhat irregularly, until toward the middle 

 of the stem they become long and convex ; this continues until the column ends 

 in an encrusting root. Dimensions of type; height of crown, 19 mm.; width, 

 10 mm. ; base, 3 mm. Length of stem, 180 mm. ; diameter at calyx, 3.2 ; at end 

 of conical enlargement, 2 mm. ; near root, 3 mm. 



