DETAILED STRATIGRAPHIC DISTRIBUTION. 123 



Geographic distribution of North American species of Ordovician Brachiopoda — Continued. 



General location. 



Occurrence in Cambrian.o 



Elkanla anibigua f Walcott) 



desiderata (Billings) 



Ida C Billings) 



Dicellomus nanus (Meek and Hayden) 



Schizambon manitouensis AValcott 



typicalis Walcott 



Acrothele levisensis Walcott 



pretiosa (Billings) 



Linnarssonella minuta (Hall and \A'hitfield) . 

 Acrotreta gemma Billings 



idahoensis Walcott 



ovalis Walcott 



Billingsella coloradoensis (Shumard) 



dice (Walcott) 



Eoorthis desmopleura (Meek) 



desmopleura nj'mpha (Walcott) 



wlchitaensis (Walcott) 



Syntrophia calcifera (Billings) 



lateralis (Whitfield) 



nundina Walcott 



Clarkella montanensis (Walcott) 



.do. 



Wyoming 



Colorado 



Nevada 



Quebec 



Quebec and New York. 



Nevada 



Newfoundland 



Nevada 



Quebec 



Minnesota 



Vermont 



Colorado and Utah 



Colorado 



.do. 



Quebec and Newfoundland. . 



Vermont 



Nevada. Utah, and Colorado. 

 Montana 



C, D3, and D?. 

 C. 



C. 



C and D^ 



A,C,D2,D3,D5,andD7. 



B, C,.D6, and D^ 



C, D3, DS D^ and DL 



a See table on pp. 114-119. 



ETJHOPEAN SPECIES. 



Geographic distribution of European species of Ordovician Brachiopoda. 



General location. 



Also occurs in — 



Volborthia recurva (Kutorga) 



Obolus? advenus Barrande 



? ancillus (Barrande) 



complexus Barrande , 



feistmanteli (Barrande) 



? mirandus (Barrande) 



? rotitzanensis Barrande 



Obolus? (Westonia?) laraellosus (Barrande). 

 Linguiella davidsoni (Barrande) . 



davisi f McCoy ) 



beberti Barrois 



? insons (Barrande) 



? simplex (Barrande) 



Siphonotreta unguiculata (Eichwald) 



verrucosa (Eichwald)., 

 Acrotreta babel Barrande. 

 ? minima ( Barrande) . 

 nicholsoni Davidson. . . 

 subconica Kutorga 



England . . 



Spain 



Bohemia. 



Upper Cambrian. 



Passage beds (Russia). 

 Do. 



Upper Cambrian. 



DETAILED STRATIGRAPHIC DISTRIBUTION OF CAMBRIAN AND ORDOVICIAN 



BRACHIOPODA. 



The follo's\dng table includes, arranged alphabetically by States or countries, more or less 

 detailed information concerning the stratigraphic distribution of the different species of Cam- 

 brian and Ordovician Bracliiopoda. 



The data available for the foreign species were not sufficient to warrant greater detail 

 than that secured by the use of generahzed sections, and there has been no attempt to keep 

 the species from any one section in a distmct column. Doubtful correlations are indicated 

 by a question mark after the locality number. 



For some of the regions in North America typical fossiliferous sections have been intro- 

 duced, giving in an adjoining column the species collected from the various horizons in the 

 section and in a third column the species collected at other places in the same general area. 

 In such tables the stratigraphic arrangement of the second column is fairly accurate; that of 

 the third may contain errors in correlation and must be regarded as merely approximate. 

 Each specific name is followed by the number of the locahty at which it occurs, and the list 

 of localities on pages 161-291 will furnish the student with all known information as to the 

 association and the stratigraphic and geographic position of the species in question. 



The numbers of the different localities identified from a given formation. State, country, 

 or place may be found by referring to the index. 



