SAGENOCRINIDAE 249 



Forbesiocrinus nobilis De Koninck and Le Hon 

 Plates XXI, fig. i; XXII, figs. 1-4; XXIII, figs. 1-8, 10; XXIV, figs. 1-27 



Plante polypiere, Witry, Mem. Acad. Imp. et Roy. Bruxelles, 1780, T. 3"", p. 18, pi. 3, fig. 3. 

 Forbesiocrinus nobilis De Koninck and Le Hon, Recherch. Crin. Carb. Belgique, 1854, p. 121, pi. 2, figs. 



2a, b. — Meek and Worthen, Proc. Acad. Nat. Sci. Philadelphia, 1865, p. 139; Geol. Surv. Illinois, II, 



1866, p. 271. — Wachsmnth and Springer, Revision Palaeocrinoidea, pt. 1, 1879, p. 52; N. A. 



Crinoidea Camerata, 1897, P- 77> P 1 - 8, figs. 6a-c. — Springer (Taxocrinus nobilis), Amer. Geologist, 



XXX, 1902, p. 90. 



Type of the genus. 



Specimens of large size. Crown elongate, rapidly spreading; with rays 

 folded widest at top of I Ax, where height to width is about I to 1.6; spread from 

 base, 1 to 3.5; cross-section quinquelobate. Rays and arms stout and deeply 

 rounded; interbrachial areas wide and depressed above iBr. Surface finely 

 pustulose. Crown of mature specimen, 90 mm. high by 45 mm. wide when 

 folded; would be much wider if rays expanded; base, 13 mm. 



IBB low, slightly visible above column, resembling a thickened proximal 

 columnal. BB large, upper angle acute, sometimes tongue-like with curving 

 sides ; post. B much the largest, angular, supporting two good-sized plates, with 

 a few smaller ones above probably extending into a tube. iBr not extending 

 higher than the axillary IBr, usually limited to about 4 to 9 plates, one large 

 with one or more ranges of smaller ones succeeding; illBr usually present. 

 RR larger than BB. IBr 3, increasing in width beyond iBr; IIBr 4; IIIBr 6 to 8, 

 with three or more bifurcations beyond; higher brachials becoming short and 

 deep. Column large, expanding" next to calyx, where the columnals are very 

 thin, 2 to the mm. for a distance of about 30 mm. ; below this alternating with 

 somewhat longer ossicles. Integument above iBr not preserved, and tegmen 

 unknown. 



The literature and morphological details of the species have been discussed under the 

 genus. In the figures of De Koninck and Le Hon the surface ornament appears somewhat 

 coarser and sharper than it is upon the. original of their figure 2.0, or upon my better pre- 

 served specimens. 



Types. The original of De Koninck and Le Hon's figure 2& (PI. XXII, figs. la, b) 

 is in the Musee Royale d'Histoire Naturelle, Brussels ; that of their figure 2a in the Museum 

 d'Histoire Naturelle, Paris. The other specimens figured are in the author's collection, and 

 were collected during a series of years by M. Ad. Piret, of Tournai. 



Horizon and locality. Lower Carboniferous, Etage 1, Tournai limestone; Tournai, 

 Belgium. 



