234 CAMBRIAN BRACHIOPODA. 



302s [U. S. National Museum]. Middle Cambrian: Dark siliceous shale in a quarry in Last Chance Gulch, south 

 slope of Mount Helena, 1.5 miles (2.4 km.) south of Helena, Jefferson County, Mont. 

 Obolus (Westonia) ella. 

 *Lingulella helena. 

 Dicellomus politus. 



302t [U. S. National Museum], Middle Cambrian: Limestone northeast of Logan, Threeforks quadrangle (U. S. 

 G. S.), Gallatin County, Mont. 

 Micromitra (Iphidella) pannula. 

 Acrotreta sp. undt. 

 Ptychoparia. 



302u [U. S. National Museum]. Upper Cambrian: Upper limestone of the Deadwood formation north of Cheever's 

 ranch, on the summit of the Bighorn Mountains, Wyo. (N. H. Darton). 

 Dicellomus nanus. 



302v [U. S. National Museum]. Ordovician: Sandstones 2 miles (3.2 km.) west of the main summit of Buffalo 

 Fork Peak [see St. John, 1877, pp. 468 and 469 and map opposite p. 324 (near station XLIX)], about 25 

 miles (40 km.) east of Jackson Lake, Uinta County, Wyo, 

 Dicellomus nanus. 



302w [U. S. National Museum]. Middle Cambrian: Limestone at Madison Mountain, Mont. 

 Acrotreta idahoensis. 

 Billingsella coloradoensia. 



302x [U. S. National Museum]. Middle Cambrian: Sandstones near the head of Powder River, Bighorn Mountains, 

 Wyo. (F. V. Hayden). 

 Obolus since. 



302y [U. S. National Museum]. Middle Cambrian: Sandstone on Johnson Creek, Bighorn Mountains, Wyo. 

 (N. H, Darton, 1902). 

 Dicellomus nanus. 



302z [U. S. National Museum]. Middle Cambrian: Limestone on Mill Creek, near Landusky, Little Rocky 

 Mountains, Chouteau County, Mont. (W. H. Weed). 

 Dicellomus nanus. 



303 [Barrande, 1879b, PL XCV]. (For stratigraphic position and association, see p. 124.) Lower Ordovician: Etage 

 d3 at Konigshof, Bohemia, Austria-Hungary. 

 *Acrotreta babel. 



303a (references follow species). (For stratigraphic position and association, see p. 124.) Lower Ordovician: 

 Etage d3 at Trubin, Bohemia, Austria-Hungary. 

 Lingulella? simplex [Barrande, 1879b, PI, CIV], 

 Acrotreta babel? [Barrande, 1879b, PI. XCV], 



30313 [Barrande, lS79b, PI. CXXVI]. (For stratigraphic position and association, see p. 124.) Lower Ordovician: 

 Etage dl in the environs of Rokitzan, Bohemia, Austria- Hungary. 

 *Obolus? rokitzanensis. 



303c (references follow species). (For stratigraphic position and association, see p, 124.) Passage beds between 

 the Upper Cambrian and the Ordovician: Suburbs of Hof, Bavaria, Germany. 



*Obolus? bavaricus [Barrande, 1868a, p. 100]. 

 *Obolus? minor [Barrande, 1868a, p. 105]. 

 *Obolus? palliatus [Barrande, 1868a, p. 105]. 

 *Lingulella cedens [Barrande, 1868a, p. 102]. 

 *Lingulella? humillima [Barrande, 1868a, p. 101], 

 *Lingulella signata [Barrande, 1868a, p. 103]. 



Lingulella wirthi [Barrande, 186Sa, p. 101]. 

 *Acrotreta inchoans [Barrande, 1868a, p. 102]. 

 *Orbiculoidea contraria [Ban-ande, 1868a, p. 104]. 

 *Orbiculoidea varians [Barrande, 1868a, p. 103]. 

 *Eoorthis bavarica [Barrande, 1868a, p. 99]. 



303d (references follow species). (For stratigraphic position and association, see p. 124.) Lower Ordovician: 

 Etage dl at Swarow, Bohemia, Austria-Hungary. 

 *Obolus? advenus [Barrande, 1879b, PL XCV]. 

 Lingulella? insons [Barrande, 1879b, PL CV]. 

 *Acrotreta? minima [Barrande, 1879b, PL XCV]. 



