DESCBIPTIONS OF SPECIES. 313 



Locality and horizon. — Crested Butte district (station 3352); Leadville limestone. 

 Aspen district (stations 2362, 2363?); Leadville limestone. 



Steaparollus tjtahensis Hall and Whitfield. 



1877. Eiiomphalus (Straparollm) utahmsis. Hall and Whitfield, U. S. Geol. Expl. 40th Par., Kept., 

 vol. 4, p. 259, pi. 4, figs. 20-23. 

 Near base of Wasatch limestone (Waverly): Dry Canyon, Oquirrh Mountains, Ogden, and 

 Logan canyons, Wasatch Eange, Utah. 

 1899. Straparollus uiahenais. Girty, U. S. Geol. Surv., Mon., vol. 32, pt. 2, p. 573, pi. 66, figs. lOa-lOe. 

 Madinon limestone: Yellowstone National Park. 



This species is represented in the Aspen region by a single specimen. It is 

 mostly exfoliated, but there is evidence of a carinatiou centrally located on the upper 

 surface of the peritreme. This specimen also differs from similar casts of St. luayus 

 by reason of its depressed spire, which is lower than the outer volution. These 

 characters ally it to St. utahensis, though it attains a much greater size than has yet 

 been observed in that species. It shows a major axis of 60 mm., and the outer 

 volution is 32 mm. thick. Straparollus lotahensis should be compared with St. vvherti, 

 to which it is closel_y related. 



Two specimens from the San Juan region (station 2381), though not well preserved, 

 can be referred with considerable certainty to this specie.?. 



Locality and horizon. — San Juan region (station 2381); Ouray limestone. Aspen 

 district (station 2362?); Leadville limestone. 



StRAPAROLLUS cf. SPERGENENSIS Hall. 



1856. Euomphalus spergenenms. Hall, Albany Inst., Trans., vol. 4, p. 19. 

 St. Louis limestone: Spergen Hill and Bloomington, Ind. 



1882. Eaomphalux KpergemnxiK. Whitfield, Am. Mus. Nat. Hist, Bull., vol. 1, p. 69, pi. 8, figs. 16-19. 

 St. Louis group: Spergen Hill, Paynters Hill, Bloomington, and EUettsville, Ind. 



1883. Euomphfilun apfrgenensix. Hall, Geol. Surv. Indiana, 12th Rept., p. .350, pi. 81, figs. 16-19. 

 St. Louis group: Spergen Hill, Lanesville, and Bloomington, Ind. 



1895. Straparullus spergenetisis. Keyes, Missouri Geol. Surv., vol. 5, p. 159. (Date of imprint 1894.) 

 St. Louis limestone: St. Louis, Mo. 



This form has been found only in the Leadville region and the identitication 

 adopted is that suggested in the list of Blue limestone species given on page 66 of 

 the Leadville monograph." A few specimens obtained from the Leadville limestone 

 show indeed a close resemblance to St. spei^genensis. They vary considerably among 

 themselves in the rise of the spire, but the limits ascribed to Hall's species in this 

 particular are not exceeded. The more elevated ones are like the specimen tigured 

 by Whitfield (loc. cit., pi. 8, figs. 16, 17, 18), but there are others which, if not 

 deformed by compression, have the spire nearly flat, closely corresponding to the 

 types of the species (fig. 19) and to the dominant form at Spergen Hill. 



o-V. S. Geol, Surv., Mou., vol. 12, 1886. 



