OBOLELLID^. 599 



Formation and locality. — Lower Cambrian: (60b) About 2, SOO feet {70Sm.) below the Mount Whyte formation and 

 200 to 300 feet (61 to 92 m.) above the Lake Louise shale, in the St. Piran sandstone [Walcott, 1908a, p. 4], at Vermilion Pass, 

 on the Continental Divide between British Columbia and Alberta, west-southwest of Castle, on the Canadian Pacific Railway, 

 Alberta, Canada. 



(53) Saiidsf»nea in the lower portion of 3d of the Waucoba Springs section [Walcott, 1908f, pp. 187 and 188], 1 mile 

 (1.6 km.) east of the Saline Valley road about 2.5 miles (4 km.) east-northeast of Waucoba Springs; (312a) sandstones 

 of 3b of the Waucoba Springs section [Walcott, 1908f, p. 187], east of the Saline Valley road east of Waucoba Springs; 

 (14p) sandstone near Resting (Freshwater) Springs, which is in the southwest corner of T. 21 N., R. 8 E., on Amar- 

 gosa River; (8b) limestone in Tollgate Canyon, about 15 miles (24.2 km.) east of White Pine, White Mountain Range; 

 and (176) shales and interbedded limestones, between massive limestones carrying Archxocyathus, at the south end 

 of Deep Spring Valley; all in Inyo County, California. 



Obolella wirrialpensis Etheridge. 

 Plate LV, figures 7, 7a-b. 



Obolella wirrialpensis Etheridge, 1905, Trans. Roy. Soc. South Australia, vol. 29, p. 248, PI. XXV, figs. 2 and 3. 



(Described and discussed as a new species. The specimen represented by fig. 2 is redrawn in this monograph, 



PI. LV, fig. 7b.) 

 Obolella wirrialpensis calceoloides Etheridge, 1905, idem, p. 249, PI. XXV, figs. 4-6. (Characterized and discussed 



as a new variety. The name placed at the head of the paragraph is "Obolella sp.," the term cafccotoiifgs being 



applied to it in the text.) 



The original description by Etheridge follows: 

 Valve (? pedicle) ovate to subquadrate, gently convex, rising dorsally into a small umbo; rounded ventrally and 

 without emargination; lateral angles rounded. Internal muscle scars hardly at all curved, diverging from one another, 

 extending far forward, and tapering to a fine point. Surface characters very marked and distinctive, consisting of a 

 series of clean-cut, flat, concentric steps, the "tread " of each step practically at right angles to its "riser; " no concen- 

 tric or radial striae of any kind . 



After a study of the type specimens of this species and several specimens that were worked 

 out of a block of the limestone received from Mr. Walter Howchin, of the University of Ade- 

 laide, I have concluded that the variety calceoloides is a narrow form of the species. There 

 are a number of intermediate forms which render it difficult to separate a distinct variety. The 

 species resembles Oholella crassa (Hall) in outline and convexity more than any other species 

 referred to the genus. 



The specific name is derived from Wirrialpa, the type locality. 



Formation and locality. — Lower? Cambrian: (316d [Etheridge, 1905, p. 248]) Limestone near Wirrialpa, 

 Flinders Range, South Australia. 



^ Obolella ? sp. undt. 



Obolella cf. atlantica Delgado, 1904, Communicagijes Commissao Servifo Geol. Portugal, tome 5, fasc. 2, p. 364, PI. 

 IV, fig. 35. (Described in French.) 



This form, Delgado states [1904, p. 364], is represented by a single specimen, which he 

 compares with Obolella atlantica Walcott. The material is too poor to base a specific deter- 

 mination upon. The photograph of the cast of the interior of a small ventral valve 4.5 mm. 

 long and 6 mm. wide indicates that the specimen may be referred to this genus, but it may 

 belong to Treniatoholus, Botsfordia, or an allied genus. 



The Obolella maculata referred to by Delgado [1904, p. 364] has in this monograph been 

 referred to AcrotJiele villaboimensis. 



Formation and locality. — Lower Cambrian: (351 [Delgado, 1904, p. 364]) Shales at Monte de Valbom, to the 

 northeast of Villa Boim, Province of Alemtejo, Portugal. 



G-LYPTIAS ■Walcott,a subgenus of OBOLELLA. 



Obolella (Olyptias) Walcott, 1901, Proc. U. S. Nat. Mus., vol. 23, p. 675. (Mentioned as below as a new subgenus.) 

 Obolella (Glyptias) Walcott, 1908, Smithsonian Misc. Coll., vol. 53, No. 4, PI. XI, and pp. 142 and 145. (Classifi- 

 cation of subgenus.) 



The subgenus Glyptias is based on the peculiar surface sculpture and the very short area. 

 Type. — Lingula (?) favosa Linnarsson. 



" Prior to the definition of this subgenus the type species was described under Lingula f Linnarsson [1869a, p. 356; 1869b, p. 406]. 



