360 TRANS. OP THE ACAD. OF SCIENCE. 



CCELIOCRINUSt (Subgenus of Poteriocrinus), White, 1863. Jour. 



Bost. Soc. iSat. Hist., vol. vii., p. 499. 

 dilatatus, Hall, 1861. Des. New Crin., Prelim. Not., p. 6.— Cceli- 



ocrinus, White, 1863. Bost. Jour. Nat. Hist., vol. vii., p. 



501. — Enc. — Burlington, Iowa, 

 subspinosus, White, 1863. Jour. Bost. Soc. Nat. Hist., vol. vii., 



p. 501. — Enc. — Burlington, Iowa, 

 ventricosus — Poteriocrinus ventricosus, Hall, 1861. Des. New 



Crinoidea, Prelim. Not., p. 6. — Caliocrinus, White, 1863. 



Bost. Jour. Nat. Hist., vol. vii., p. 501. — Enc. — Burlington, 



Iowa. 



COMAROCYSTITES, Billings, 1854. Canad. Jour., vol. ii., p. 270. 

 punctatus, Billings, 1854. Canad. Jour., vol. ii., p. 270. — 1857. 

 Geol. Surv. Canada, p. 288. — 1858. Can. Org. Rem., Dec. 

 iii., p. 61, pi. 5.— Trent. — Ottawa, Canada. 



CONOCRINUS, v. Alloprosallocrinus. 



COTYLEDONOCRINUS^S (Subgenus of Dichocrinus), Casseday & 

 Lyon, 1860. Pr. Amer. Acad. Arts & Sci., vol. v., p. 26. 

 pentalobus, Casseday & Lyon, 1860. Proc. Amer. Acad. Arts & 

 Sci., vol. v., p. 26. — Kas. — Grayson Co,, Kentucky. 



CRASSIBRACHIATUS, Hall, 1860. Geol, Iowa, Sup., p. 60. 



CRINOCYSTITES, Hall, 1864. Ace. New or little known Fossils 

 Niag. Group, p. 13. — Niag. — Racine, Wisconsin* 



chrysalis, Hall, 1864. Ace. New or little known Foss. Niag. Gr., 



p. 14. — Niag. — Racine, Wisconsin. 

 (?)rectu8, Hall, 1864. Ace. New or little known Foss. Niag. Gr., 



p. 14. — Niag. — Racine, Wisconsin. 



CRUMEN.ECRINITES,* Troost, 1850. List Crin. Tenn. Proc. Am. 

 Assoc. Camb. Meet., p. 62. 

 ovalis,* Troost, 1850. List Crin. Tenn. in Proc. Amer. Assoc. 

 Camb. Meet., p. 62. — Tennessee. 



CTENOCRINUS, Bronn, 1840. Leonh. und Bronn, Jahrb., p. 542, 

 pi. 8. — Macrostylocrinus, Hall, 1852. Pal. N. York, vol. 

 ii., p. 203. — CrrocRiNUs,t Roomer, 1860. Sil. Faun. West. 

 Tenn., p. 46. 



J It is questionable whether the characters given by the author are suf- 

 ficiently distinctive to warrant us in separating this group from Poterio- 

 crinus. They are, however, quite as important, as we find in some of the 

 Subgenera of Actinocrinus, Dichocrinus, and Rhodocrinus, now recognized 

 by some of our prominent palaeontologists. 



§ This Subgenus, proposed by Casseday and Lyon, presents a very close 

 analogy with Dichocrinus. The formula given by the authors is : Basal 

 pieces, 2; Primary radials, 3X5; Secondary radials, 2X10; Arms, 20; Inter- 

 radials, 3X5; Anal piece, none. It seems to differ from Dichocrinus chiefly 

 in the absence of an anal piece in the first series above the base, and there 

 may be some reason for doubt whether this be a permanent or merely an 

 accidental character. 



t In the Trans, of the Albany Institute (vol. iv., p. 207), Prof. Hall has 

 pointed out the identity of Cytocrinus, Kcem., with Macrostylocrinus, Hall, 

 and in the same place Prof. H. remarks that " the G-enus Ctenocrinus of 

 Bronn, as described by Pictet, possesses a structure resembling or identi- 



