346 PROCEEDINGS OF THE ACADEMY OF [1879. 



*1861. ? Graphiocrinus carbonarius Meek & Worthen. (Scaphiocr. carbonarius.) 

 Proc. Acad. Nat. Sci. Phil., p. 140; Geo!. Rep. 111., vol. v. p. 562, pi. 24, 

 fig. 2. Coal Measures. Springfield, 111. 



1853. Graphiocr. encrinoides De Koninck & Lehon. Type of the genus. Recherch. 

 Crin. Belg., p. 117, pi. 4, fig. 15, 15 a, b. Mountain limest. Subcarb. Tour- 

 nay, Belg., and Bristol, Eng. 



*1873. Graphiocr. McAdamsi Worthen. (Scaphiocr. McAdamsi.) Geol. Rep. 111., 

 vol. v. p. 495, pi. 15, fig. 2. Keokuk limest. Subcarb. Jersey Co., 111. 



*1869. Graphiocr. rudis Meek & Worthen. (Scaphiocr. rudis.) Proc. Acad. Nat. 

 Sci. Phil., p. 139; Geol. Rep. 111., vol. v. p. 412, pi. 1, fig. 1. Upper Bur- 

 lington limest. Subcarb. Burlington, Iowa. 



*1858- Graphiocr. simplex Hall. (Scaphiocr. simplex.) Geol. Rep. Iowa, vol. 

 i. pt. ii. p. 551, pi. 9, Fig. 10. Burlington limest. Subcarb. Burlington, 

 Iowa. 



*1861. Graphiocr. spinobrachiatus Hall. (Scaphiocr. spinobrachiatus.) New 

 Pal. Crin., p. 8; Bost. Journ. Nat. Hist., p. 306. Lower Burlington limest. 

 Subcarb. Burlington, Iowa. 



*1869. Graphiocr. striatus Meek & Worthen. (Scaphiocr. striatus.) Proc. Acad. 

 Nat. Sci. Phil., p. 142; Geol. Rep. 111., vol. v. pi. 2, fig. 11. Lower Bur- 

 lington limest. Subcarb. Burlington, Iowa. 



*1861. Graphiocr. tortuosus Hall. (Scaphiocr. tortuosus.) Desc. New Pal. Crin., 

 p. 7; Bost. Journ. Nat. Hist., p. 309. Upper and Lower Burlington limest. 

 Subcarb. Burlington, Iowa. 



*1861. Graphiocr. Wachsmuthi Meek & Worthen. (Scaphiocr. Wachsmuthi.) 

 Proc. Acad. Nat. Sci. Phil., p. 141 ; Geol. Rep. 111., vol. iii., p. 488, pi. 16, 

 fig. 7, a, b. Lower Burl, limest. Subcarb. Burlington, Iowa. 



B. Subgenus BURSACRINUS Meek & Worthen. 



1861. Bursacrinus M. & W. Proc. Acad. Nat. Sci. Phil., p. 136. 



1862. Bursacrinus White. Proc. Bost. Soc. Nat. Hist., vol. ix. p. 11. 

 1868. Bursacrinus M. & W. Geol. Rep. 111., vol. iii. p. 478. 



Body rapidly spreading to the top of the first division of the 

 arms. Calyx, in the known species, small and turbinate, closely 

 agreeing with Graphiocrinus in its general construction, but the 

 basals comparatively larger, the posterior one much higher and 

 truncated. Radials and brachials smaller, and the single anal 

 plate, which here also reaches beyond the plane of the radials, ex- 

 tends at least in the typical species as far as to the lower portion 

 of the first arm plates. The best distinction, however, and that 

 by which Bursacrinus is easily recognized, is found in the arms, 

 which are branching instead of simple, broad, flat, and in contact 

 laterally. Between the first bifurcation of the rays on the brachial 

 pieces and the next division above, the arms are very wide, flat, 

 and composed of from six to eight short wedge-form pieces which 

 are squarely truncated on each side. In the division above, the 



