300 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 53 



The stratigTaphic position of IV. ? gracile is in the central 

 portion of the Lower Cambrian terrane of western Nevada and 

 southeastern Cah'fornia beneath the great Archaocyathus hmestone. 

 It is associated with Olenellus fremonti in the massive quartzitic 

 sandstone series 2,500 feet above the horizon of Nevadia iveeksi, and 

 1,200 feet or more below the upper beds of the Lower Cambrian 

 carrying Olenellus gilberti. At Vermilion Pass, Alberta, numerous 

 specimens of the cephalon of this species [pi. 38, figs. 17-20] occur 

 in a hard, brownish-gray sandstone of the St. Piran formation, about 

 2,000 feet below the Mt. Whyte formation and 250 feet above the 

 Lake Louise formation. With the cephalon for comparison, there 

 do not appear to be specific differences between the specimens from 

 Nevada and Alberta, localities 1,450 miles distant from each other. 



Near Resting Springs (locality No. I4p) the following species 

 are associated with W. gracile: Cystid plates, Lingidella {Lin- 

 gulepis) rozvei Walcott, Billingsella hkna n. sp., Obolella vermil- 

 toncnsis n. sp., and Olenellus fremonti Walcott; in Nevada (locality 

 No. iv) : Arcbceocyathiis ? sp., Kutorgina cingulata (Billings), K. 

 penigata Walcott, Siphonotrcta ? dubia n. sp., Sivantonia weeksi 

 Walcott, Swantonia ? sp., Stenotheca cf. elongata Walcott, Steno- 

 theca cf. rngosa Walcott, Ptychoparia sp., and Olenellus argentus 

 Walcott; at Vermilion Pass (locality No. 60b) : Obolella zerniilion- 

 ensis n. sp., Orthotheca adamsi, n. sp. 



Formation and Locality. — Lower Cambrian: Silver Peak for- 

 mation [see Walcott, igd&c, p. 185] at the following localities: (14P) 

 quartsitic sandstones near Resting {Fresh Water) Springs, which 

 is in the southzvest corner of T. 21 N., R. 8 E., on the Arniagosa 

 River; (8) arenaceous shales and shaly sandstones 3 miles (4.8 km.) 

 above Tollgate Canyon, White Mountain Range; (53) sandstones 

 in the lower portion of 3d of the Waucoba Springs section [Wal- 

 cott, 1908/, pp. 187 and 188], I mile (1.6 km.) east of Saline Valley, 

 road about 2.5 miles (4km.) east-northeast of Waucoba Springs; 

 (176 and 178a) in arenaceous shales apparently lying between mas- 

 sive limestones carrying Archseocyathus, at the south end of the 

 Deep Spring Valley, about 20 miles (32 km.) east-southeast of Big 

 Pine in Owens Valley; and (177) shales in low hills 3 miles (4.8 

 km.) west of the Deep Spring Valley ; all in Inyo County, California. 



(iv) arenaceous shales 3 miles north of Valcalda Spring and 4 

 miles (6.4 km.) northwest of Drinkwater Mine, Silver Peak quad- 

 rangle, Esmeralda County, Nevada. 



