Klem — Revision of the Palaeozoic Palaeechinoidea. 59 



the Platte River, Neb.; Vermilion Co., 111., and Kansas 

 City, Mo. 



24. Aechaeocidaris trudifer White. 



1874. Archaeocidaris trudifer. White, Prelim. Rep. Inv. 

 Foss., p. 17. 



1876. Archaeocidaris trudifer. White, Powell's Rep. Geol. 

 Uinta Mts., p. 89. 



1877. Archaeocidaris trudifer. White, U. S. Geol. Surv. 

 W. 100 Mer., vol. 4, p. 104, pi. 6, figs. 8 a, b. 



1889. Archaeocidaris trudifera. Miller, N. Amer. Geol., 



p. 225. 

 1895. Archaeocidaris trudifer. Keyes, Proc. Iowa Acad. 



Sci., vol. 2, p. 191. 

 1900. Archaeocidaris trudifer. Beede, Univ. Geol. Surv. 



Kas., vol. 6, p. 47, pi. 8, tig. 10. 

 1903. Archaeocidaris trudifer ? Girty, U. S. Geol. Surv. 

 Professional Paper No. 16, p. 330. 

 Areolar surface plain. Central tubercle small, surrounded 

 by a slightly raised ring and a second ring so much elevated 

 as to form a little cup with an expanded rim. 



Primary spines slender and terete, tapering gradually near 

 the apex. Surface of the spine immediately above the basal 

 ring smooth, but further on ornamented with numerous fine 

 spinules in an imperfect spiral. 



Geological formation and locality: Coal measures, Camp 

 Apache, Arizona; Confluence of the Grand and Green rivers, 

 Utah; Topeka, Kas.; Leadville district, Colo. 



25. Archaeocidaris urei Fleming. 



1793. Echinus . Ure, Hist. Rutherglen, pi. 16, figs. 



7, 8. 

 1828. Cidaris Urii. Fleming, Brit. Animals, p. 478. 



1843. Cidaris Benburbensis . Portlock, Geol. Rep., p. 352, 

 pi. 16, figs. lOa-d. 



1844. Echinocrinus Urii. M'Coy, Foss. of Ireland, p. 174, 

 pi. 27, -fig. 1. 



