155 Cren. 



pi. 3, f. 5 ; not well enough preserved to remove all doubt as 

 to the genus. Found by the Revd. Mr. Moore of Greensburg, 

 Westmoreland Co., Pa., in black shale above the 4th coal bed 

 at base of Pittsburgh series {Barren Measures) ; shale covered 

 with marine shells ; plant therefore perhaps a seaweed. Les- 

 quereux found at the same spot many fragments of ferns and 

 reeds, especially a Sphenopteris. Top of Allegheny series of 

 coal measures. — XIII-XIV, 



Crenipecten caroli^ ( Aviculopecten caroli, Winchell, Proc. 

 Acad. Nat. Sci. Philada. 1863.) Redescribed and figured in 

 Hall's Pal. N. Y. vol. 5, part 1, 1884, page 29, plate 9, fig. 5, in 

 which (a cast) the small spine-like projections from the con- 

 centric lines (described in WinchelPs original paper) do not 

 appear. More circular than Amc. striatus^ blunter beak, 

 stronger rays. Smaller wings than Avic, elongatus. Waverly 

 yellow sandstone^ Newark, Ohio. X? — Recognized by J. Hall, 

 Dec, 1888, in Specimen 9577 of Randall's Collections at War- 

 ren Pa. IX-Xf — See Appendix^ under the original name 

 Aviculopecten caroli. 



Crenipecten winchelli. Hall, Palaeontology of New 1 ork, 

 Vol. 5, part 1, Lamellibranchs, 1884, page 89, plate 9, figs. 1, 2, 

 4, 25 to 30. [Aviculopecten winchelli^ Meek, Pal. Ohio, Vol. 

 2, 18^5, p. 296, pi. 15, figs. 50,56.) Recognized by J, Hall, Dec, 

 1888, in Pennsylvania Specimen 9550 (Report 000) of Ran- 

 dall's Collections at Warren, Pa., from the Ohemung-Catskill ? 

 ( VII I- IX?) See Appendix. 



Crepicephalus. See Ptychoparia haguei, its type species. 

 Middle Cambrian, M, C. 



Crepicephalus iowensis. See Ptychoparia iowensis. Mid- 

 dle Cambrian. M. C. 



Crinoidea. Stone lilies. |An order of sea animals, mostly 

 growing like plants, fwith jointed flexible stems, supporting 

 cup shaped heads, set with flexible jointed arms, fringed with 

 jointed flexible hair, for the gathering of food. Six families, 

 Cyathocrinidm^ Actinocrinidoe^ Calceocrinidoe^ AncyrocrinidcB^ 

 Edriocrinidoe^ Brachiocrinidce^ include a large number of 

 genera, with a very great number of named species. They 

 grew like submarine prairies, and were sometimes overwhelmed 



