826 



NORTH AMERICAN INDEX FOSSILS. 



Cespitose — matted, tangled or growing 

 in low tufts. 



Cnagrin formation — upper Devonic of 

 Ohio. 



Chamber — an enclosed space or cell. 

 In cephalopods, the space between 

 two septa. 



Chambersburg limestone — middle Or- 

 dovicic of Pennsylvania. 



Charlestown sandstone — middle Car- 

 bonic of Appalachians. 



Chase formation — Permic of Kansas. 



Chattahoochee formation — middle Oli- 

 gocenic of the Gulf coast. 



Chattanooga black shale — lower Missis- 

 sippic of the Appalachians. 



Chautauquan series — part of upper De- 

 vonic of eastern U. S. 



Chazyan — general term for middle Or- 

 dovicic. 



Chazy limestone — middle Ordovicic of 

 eastern North America. 



Cheeks — in trilobites, lateral portions 

 of the cephalon, divided into fixed 

 and free cheeks (cf. fixed, free). 



Chela (plural chelce) — pincer-like claw 

 terminating some of the legs of crus- 

 taceans (see Figs. 1692, 1694). 



Chelate — bearing chelae. 



Chelopod — see II., 388. 



Chemung — upper Devonic of North 

 America. 



Cherokee shale — base of Coal Measures 

 of Kansas. 



Chert — a compact siliceous rock of or- 

 ganic or chemically precipitated, ori- 

 gin, e. g., flint. 



Chesapeake group — middle Miocenic of 

 Atlantic coast. 



Chester group — upper Mississippic of 

 central U. S. 



Chickamauga limestone — middle Ordo- 

 vicic of southern Appalachians. 



Chickasawan formation — lower Eocenic 

 of Gulf coast. 



Chickies quartzite — lower Cambric of 

 Pennsylvania. 



Chico series — Cretacic (chiefly Colo- 

 radoan) of Pacific coast. 



Chilhoivee series — lower Cambric of 

 southern Appalachians. 



Chilidiiim — a convex plate covering the 

 chilyrium; probably secreted by the 

 posterior edge of the dorsal mantle 

 lobe. 



Chilyrium — a triangular opening under 

 the beak of the brachial valve in 

 those brachiopods in which that valve 

 is furnished with a high hinge area, 

 as in the Protremata {e. g., Syntro- 

 phia). 



Chipola marls — middle Oligocenic of 

 Gulf states. 



Chiques quartzite — see Chickies. 



Chitin — a horn-like substance, found in 

 the hard parts of all the articulated 

 animals, such as beetles and crusta- 

 ceans, and when pure consisting of 

 CisH^eN^Oio. 



Chitinous — composed of chitin. 



Chondrophore — see resilifer. 



Chonopectus sandstone — division of 

 Kinderhook of upper Mississippi Val- 

 ley. 



Choptank formation — middle Miocenic 

 of eastern U. S. (division of Chesa- 

 peakean). 



Choiiteauan — general name for the Kin- 

 derhook division of the lower Missis- 

 sippic. 



Chouteau limestone — upper division of 

 the Kinderhook of Mississippi Valley. 



Cicatrix — a scar. 



Cimarron formation — upper Permic of 

 Kansas. 



Cincinnati group (Cincinnatian) — gen- 

 eral term for the upper part of the 

 upper Ordovicic. 



Cirri — lateral appendages to the stem 

 of crinoids. 



Cisco formation — upper Carbonic of 

 Texas. 



Claggett formation — middle Cretacic of 

 Canada. 



Claiborne — middle Eocenic of the Gulf 

 region. 



Clastic — consisting of fragments, e. g., 

 rocks composed of fragments of older 

 rocks. 



Clavate — club-shaped. 



