OBOLIDiE. 



467 



having the surface marked by radiating hnes that extend from the umbo with a gentle curva- 

 ture toward the sides and front of the shell, so as to terminate at right angles to the margin, 

 very much as in Oholus (Westonia) Jinlandensis (PI. XLVTII, figs. 3 and 3a). 



In the Blacksmith Fork section of the Middle Cambrian terrane in the Wasatch Moun- 

 tains of northern Utah 0. {W.) wasatchensis occurs 1,590 feet higher in the section than 

 0. (TF.) dla. 



The specific name is derived from its occurrence in Wasatch Canyon, Utah. 



Formation and locality. — Middle Cambrian: (34u) Shales about 950 feet (289.6 m.) above the Cambrian quartzitic 

 beds, 2 miles (3.2 km.) southeast of Muski-at Spring, on the northwest face of Grantsville Peak, Stansbury Range, 

 Tooele County; and (33t) shale about 1,500 feet (457.2 m.) above the Brigham quartzite, 1 mile (1.6 km.) northwest 

 of Geneva (Copenhagen), east of Brig- 

 ham, Boxelder County; both in Utah. 



(54c[) Drift block supposed to have 

 come from the horizon of Locality 32x; 

 (32x) about 1,700 feet(518.2 m.) above 

 the Brigham quartzite [Walcott, 190Sa, 

 p. 8], in shales correlated with the 

 shales forming 2d of the Bloomington 

 formation in Blacksmith Fork Canyon 

 [Walcott, 1908f, p. 195]; and (33]) 

 about 2,300 feet (701 m.) above the 

 Brigham quartzite; all in Wasatch 

 Canyon, east of Lakeview Ranch, 5 

 miles (8 km.) north of Brigham, Box- 

 elder County, Utah. 



(54h) About 3,140 feet (957.1 m.) 

 above the Brigham quartzite fWalcott, 

 1908a, p. 8] and 1,050 feet (320 m.) 

 below the Upper Cambrian in the lime- 

 stones forming la of the Bloomington 

 formation [Walcott, 1908f, p. 194]; and 

 (54k) about 2,100 feet (640 m.) above 

 the Lower Cambrian and 2,100 feet 

 (640 m.) below the Upper Cambrian 

 in the shales forming 2d of the Bloom- 

 ington formation [Walcott, 1908f, p. 

 195] ; both in Blacksmith Fork Canyon, 

 about 10 miles (16.1 km.) east of Hy- 

 rum. Cache County, Utah. 



(55d) About 2,000 feet (609.6 m.) above the Cambrian qua,rtzitic beds, in a shale which is probably to be referred 

 to the Bloomington formation [Walcott, 1908a, p. 7], on the south side of Twomile Canyon near its mouth, 2 miles 

 (3.2 km.) southeast of Malade, Oneida County, Idaho. 



E D 



Figure il.—Obolus {Westonia) wasatchensis Walcott. A, Elongate ventral valve, the type 

 specimen (U. S. Nat. Mus. Cat. No. 51733a). B, Interior view of an elongate ventral valve 

 (U.S. Nat. Mus. Cat. No. 51737a). C, Interior of a broken, flattened ventral valve (U.S. Nat. 

 Mils. Cat. No. 51734b). D, Exterior of dorsal valve (U. S. Nat. Mus. Cat. No. 61734a). 

 E, Interior of a flattened dorsal valve (U. S. Nat. Mus. Cat. No. 51734c). F, Interior of a 

 dorsal valve (U. S. Nat. Mus. Cat. No. 51734d). 



The specimens represented by figures ilA and 41B are from Localities 54q and S5d, respec- 

 tively; and those represented by figures 41C-F are from Locality 54k. Figures 41A and 41D are 

 copied from Walcott [190Sd, PI. VIII, figs. 1 and la, respectively). 



I 



Obolus (Westonia) wimani Walcott. 



Plate XLVIII, figures 5, 5a-b. 



Lingula? sp. No. 1, Wiman, 1902, Bull. Geol. Inst. Univ. Upsala, vol. 6, pt. 1, No. 11, p. 51, PI. II, fig. 36. 



mentioned.) 

 Lingulella? sp. No. 1, Wiman, 1902, idem, p. 52, PL II, fig. 30. (Locality mentioned. 



fig. 30 is redrawn in this monograph, PL XLVIII, fig. 5.) 

 Lingulella? sp. No. 2, Wiman, 1902, idem, p. 52, PL II, fig. 31. (Locality mentioned. 



fig. 31 is redrawn in this monograph, PL XLVIII, fig. 5a.) 

 Lingulellaf sp. No. 7, Wiman, 1902, idem, p. 52, PL II, fig. 32. (Locality mentioned. 



fig. 32 is redrawn in this monograph, PL XLVIII, fig. 5b.) 

 Obolus ( Westonia) wimani Walcott, 1905, Proc. U. S. Nat. Mus., vol. 28, p. 337. (Discussed essentially as below as a 



new species.) 



The general form of this species is not unlike that of Oholus ( Westonia) lottnicus (Wiman) 

 (PL XLVIII). The cardinal slopes of the ventral valve are more rounded, which makes the 

 valve broader near the center. AU of the specimens are also smaller. The surface markings 



(Locality 

 The specimen represented by 

 The specimen represented by 

 The specimen represjnted by 



