PATEKINID^. 



343 



(STc") About 2,500 feet (762 m.) above the Lower Cambrian and 2,475 feet (754 m.) below the Upper Cambrian 

 in the limestone forming 1 of the Stephen formation [Walcott, 1908f, p. 209]; and (58z) about 1,875 feet (572 m.) above 

 the Lower Cambrian and 3,100 feet (945 m.) below the Upper Cambrian in the limestone forming 2b of the Stephen 

 formation [Walcott, 1908f, p. 211]; both on Mount Bosworth, north of the Canadian Pacific Railway between Hector 

 and Stephen, on the Continental Divide between British Columbia and Alberta, Canada. 



t/ 



MicROMiTEA sp. undt. (Walcott). 



Plate III, figure 7. 



Iphidea sp. undet., Walcott, 1899, Mon. U. S. Geol. Survey, vol. 32, pt. 2, p. 449, PL LX, fig. 6. (Described and 

 discussed as below as an undetermined species. The specimen represented by fig. 6 is redrawn in this mono- 

 graph, PL III, fig. 7.) 



IpMdella sp. undt., Walcott, 1905, Proc. U. S. Nat. Mus., vol. 28, p. 305. (Description and discussion copied from 

 preceding reference.) 



Dorsal valve semicircular, slightly convex. Hinge line somewhat shorter than the width 

 of the shell below; nearly straight, the rostral angle about 180°. Beak small, not elevated. 

 Surface ornamented by extremely fine, radiating, and undulating concentric striae that can 

 be seen in detail only with a strong magnifying glass. Shell substance horny. 



This form is associated with Micromitra sculptilis (jVIeek) and, judging from external 

 characters, is closely related to it. The surface ornamentation is of the same character, and, 

 in the absence of the ventral valve, it is difficult to distinguish any specific characters on which 

 to base a new species, although the shell is much larger than that of M. sculptilis. 



Formation and locality. — Middle Cambrian: (302b) Limestones near Crowfoot Ridge, GaUatin quadrangle 

 (U. S. Geol. Sm'vey), Yellowstone National Park, Wyoming. 



PATEBINA Beecher,o subgenus of MICROMITRA. 



IJPater, father.] 



Kutorgina Dall (in part) [not Billings], 1877, Bull. U. S. Nat. Mus. No. 8, pp. 40-41. (Includes reference to speci- 

 mens now referred to Micromitra (Paterina) . ) 



Kutorgina Walcott (in part) [not Billings], 1886, Bull. U. S. Geol. Survey No. 30, pp. 101-102. (Genus Kutorgina 

 described, but description also includes reference to specimens now referred to Micromitra, Micromitra (Paterina), 

 and Micromitra (Iphidella).) 



Paterina Beecher, 1891, Am. Jour. Sci., 3d ser., vol. 41, p. 345, and footnote. (Gives reasons for proposing Paterina as 

 a new genus.) 



Paterina Beecher, Hall and Clabke, 1892, Eleventh Ann. Rept. State Geologist New York for 1891, p. 247. (De- 

 scribed.) 



Iphidea Billings, Hall and Clarke, 1892, idem, p. 249. (Described and accompanied by figures of specimens referred 

 to the subgenus Paterina.) 



Paterina Beecher, Hall and Clarke, 1892, Forty-fifth Ann. Rept. New York State Museum for 1891, p. 563. (Copy 

 of Hall and Clarke, lS92a, p. 247.) 



Iphidea Billings, Hall and Clarke, 1892, idem, p. 565. (Copy of Hall and Clai-ke, 1892a, p. 249.) 



Kutorgina Hall and Clarke (in part) [not Billings], 1892, Nat. Hist. New York, Paleontology, vol. 8, pt. 1, pp. 

 90-94. (Copies Walcott's description [1886, pp. 101-102] and discusses genus, but description and discussion 

 also include reference to specimens now referred to Micromitra, Micromitra (Paterina), Micromitra (Iphidella), 

 Protorthis, and Billinqsella.) 



o The synonymy for this subgenus does not give a complete record of the various genera under which the species now included in Paterina were 

 formerly placed; it includes only those references in which the subgenus is discussed or described. For the sake of completing the record the remain- 

 ing mere generic references are here listed: 



Obolus Billings (ISGlb, p. 6; lS61c, p. 946; 1862e, 



p. 218; 1863, p. 284]. 

 Obolella HoU [1865, p. 102]. 

 Oboiaia f Davidson [1866, p. 62]. 

 Kutorgina Davidson [1868, p. 312; 1871, p. 342). 

 Obolella Phillips [1871, p. 68). 

 Iphidea BilUngs [lS72b, p. 477; 1874, p. 76], 

 Obolellus? Eoemer [1876, PI. 11, figs. 6a-d]. 

 Obolella Dall [1877, p. 41]. 

 Iphidea Billings [1882, p. 13]. 

 Kutorgina Davidson [1883, p. 212). 

 Kutorgina Walcott [1884b, p. 19]. 

 IpMdea Walcott [1886b, p. 100]. 



Iphidea Oehlert [1887, p. 1270]. 



Kutorgina Dwight [1889, p. 145]. 



Kutorgina Walcott [1890, p. 36). 



Kutorgina Dwight [1891, p. 105]. 



Iphidea Walcott [1891a, p. 608]. 



Kutorgina Walcott [1891a, p. 609]. 



Kutorgina Moberg [1892b, p. 112]. 



Platijceras Tate [1892, p. 184). 



Ipliidea Hall and Clarke [lS92e, PI. IV, figs. 6 and 7). 



IpMdea Grabau [1900, p. 617]. 



Kutorgina Matley [1902, p. 145]. 



Micromitra Clark and Mathews [1900, p. 252]. 



