398 SMITHSONIAN INSTITUTION 



Types. Miller and Gurley's original is in the Walker Museum, University of Chicago. 

 The other specimens figured and used in study are in the author's collection. 



Horizon and locality. Lower Carboniferous, Keokuk Group ; all from two colonies at 

 Indian Creek, Montgomery County, Indiana, at a horizon below that of the Crawfords- 

 ville bed. 



Taxocrinus colletti White 

 Plates XXI, fig. 4; LI 7 , fig. 11; LVI, figs. 1-11 ; LVII, figs. 1-10 



Taxocrinus multibrachiatus var. colletti White, 2d Ann. Rep. Stat, and Geol. Indiana, 1880, p. 506, pi. 6, 

 fig. 3 (another edition 1881, p. 138). 



Taxocrinus colletti, Miller and Gurley, Bull. 3, Illinois St. Mus., 1894, p. 49; ibid., Bull. 8, 1896, p. 56. — 

 Zittel-Eastman, Textbook Paleontology, 1913, p. 206, fig. 307. 



Forbesiocrinus meeki, Quenstedt (not Hall) ; Handbuch Petrefaktenkunde, 1885, p. 946, pi. 75, figs. 24, 25. 



Taxocrinus meeki, Von Zittel (not Hall), Grundziige Palaeontologie, 1895, p. 138, fig. 273; Zittel- 

 Eastman, Textbook Palaeontology, 1896, p. 164, fig. 273. 



Taxocrinus splendens Miller and Gurley, Bull. 8, Illinois St. Mus., 1896, p. 61, pi. 5, figs. 3, 4; Springer, 

 Jour. Geology, XIV, 1906, p. 489. 



Taxocrinus multibrachiatus collectionum. 



Not Forbesiocrinus multibrachiatus Lyon and Casseday, Amer. Jour. Sci. (2) XXVIII, 1859, p. 235. 



A representative and highly characteristic species of the genus Taxocrinus. 

 Specimens attaining a large size. Crown elongate, moderately rounded below, 

 widest about the third bifurcation, and usually infolding shortly above the 

 fourth; height to width about 1.4 to 1. Calyx 1 to 2.5 at I Ax in average large 

 specimen; in smaller ones narrower, 1 to 1.2; spread from base, 1 to 3.2. Rays 

 strong and prominent, broadly convex in lower divisions ; arms tapering evenly 

 and without marked change until beyond the third axillary, and not strongly 

 divergent ; sutures strongly arcuate. Interbrachials well-developed ; areas 

 depressed, fairly wide, elongate, with numerous strong plates in lower portion. 

 Surface covered with a very close pustulose or sometimes slightly wrinkled 

 ornamentation. Dimension of representative large specimen: Crown, 54 mm. 

 high; 35 mm. wide; base, 9 mm.; calyx, 11 mm. high by 28 wide. Small speci- 

 mens : Crown, 10 mm. high by 7 wide ; base, 3 ; calyx, 6 by 6.5 mm. 



IBB very low, not within BB, but visible only as a thin line like a top 

 columnal. BB small, less than half the size of RR, low, and obtuse-angled 

 except post. B ; this plate is very high, its distal margin well rounded in a dorso- 

 ventral direction, with a shallow scar for attachment of first one or two anal 

 plates extending more than half-way down its outer surface; usually rather 

 to the right of the median line, but not encroaching on r. post. R. RR about 

 the form and size of succeeding IBr, which are half as long as wide. IBr 3; 

 IIBr 3 in most cases, frequently 4, nearly as large as IBr and of similar form; 

 IIIBr 5 or 6 inner, 8 or 10 outer; the next division proportionally larger. 

 Brachials above IIBr proportionally shorter than below, being often only one- 

 third as long as wide. iBr 6 to 10 strong plates, with rounded and crescentic 

 distal margin connecting with finely plated perisome at the inner edge; in 

 young specimens there may be only 1 or 2 plates, or none at all. There are 



