DESCRIPTIONS OF SPECIES. 347 



1872. Syntrielasma hemiplicata. Meek, U. S. Geol. Surv. Nebraska, p. 177, pi. 6, flgs. la, b; pi. 8, figa. 



12a, 6. 

 Upper Coal Measures: Nebraska City, Wyo., and Bennett's Mill, Nebr. 

 Coal Measures: Illinois, Iowa, Missouri, Kansas. 



1873. Syntrielasma hemiplicata. Meek and Worthen, Geol. Surv. Illinois, Eept., vol. 5, p. 571, pi. 26, 



fig. 20. 

 Upper Coal Measures: 12 miles north of Vandalia, 111. 



1882. Camerophoria gifordi. "Worthen, Illinois State Mus. Nat. Hist., Bull. No. 1, p. 39. 

 Middle Coal Measures: Near Alta, Peoria County, 111. 



1883. Camerophoria gifordi. Worthen, Geol. Surv. Illinois, Eept., vol. 7, p. 318, figs. a-c. 

 Middle Coal Measures: Near Alta, Peoria County, 111. 



1883. Syntrielasma hemiplicata. Kayser, Richtofen's China, vol. 4, p. 179, pi. 24, flgs. 2, 3. 

 Upper Carboniferous: Lo-Ping, China. 



1884. Syntrielasma hemiplicata. White, Geol. Surv. Indiana, 13th Kept., p. 131, pi. 26, figs. 15-18. 

 Coal Measures: Indiana. 



1892. Enteletes hemiplicata. Hall and Clarke, Int. Study of Brach., pt. 1, pi. 12, figs. 18-21. 



Coal Measures: Winterset, Iowa; Kansas City, Mo. 

 1892. Enteletes hemiplicata. Hall and Clarke, Pal. New York, vol. 8, pt. 1, pp. 215, 226, pi. 7 A, flgs. 44-52. 



Upper Coal Measures: Kansas City, Mo.; Winterset, Iowa. 

 1895. Syntrielasma hemiplicata. Keyes, Missouri Geol. Surv., vol. 5, p. 76, pi. 39, flgs. 8a-d. (Date of 

 imprint, 1894.) 



Upper Coal Measures: Kansas City, Mo. 

 1900. Enteletes hemiplicata. Beede, Univ. Geol. Surv. Kansas, Eept., vol. 6, p. 91, pi. 12, flgs. 6, 6b. 



Upper Coal Measures: Kansas City, Independence, Ida, Edwardsville, Eudora, Lawrence, 

 Lecompton, Topeka, Kans. 



Though not occurring elsewhere in our Colorado collections, this species is found 

 in considerable abundance at Sinbads Valley (station 2285). The - specimens are 

 badly crushed, but appear to be typical in every way. 



Locality and horizon. — Dolores River region, Sinbads Valley (station 2285); 

 top of the Hermosa formation. 



DERBYA Waagen, 1884. 



Derby A ckassa Meek and Hay den. 



1852. Orthis umhraeulum f Hall, Stansb. Exped. Great Salt Lake, p. 412, pi. 3, fig. 6. 



Carboniferous: Missouri River, above Fart Leavenworth. 

 1852. Orthis umhraeulum? Owen, Geol. Surv. Wisconsin, Iowa, and Minnesota, pi. 5, fig. 11. 



Carboniferous: Missouri River, near mouth of Keg Creek, and at Council Bluffs. 

 1852. Orthis arachnoidea. Eoemer (non Phillips), Kreid. von Texas, p. 89, pi. 11, flgs. 9a, b. 



Carboniferous: San Saba Valley, Tex. 



1857. Orthis arachnoidea. Hall, Mexican Boundary Survey, i^l. 20, flg. 3. 



1858. Orthisina crassa. Meek and Hayden, Acad. Nat. Sci. Philadelphia, Proc, p. 261. 

 Coal Measures: Leavenworth, Kans. 



1858. Orthis crenistria. Marcou, Geol. North America, p. 49. 



Mountain limestone: Pecos Village, New Mexico. 



1859. Orthisina crassa. Meek and Hayden, Acad. Nat. Sci. Philadelphia, Proc, p. 26. 

 Coal Measures: Leavenworth, Kans. 



