FOURTH CONTRIBUTION TO NOMENCLATURE OF 

 CAMBRIAN FOSSILS 



By CHARLES ELMER RESSER 



Curator, Diz'isioii of Invertebrate Paleontology, 

 U. S. National Museum 



This is the fourth paper in a series dealing with nomenclatural 

 changes necessary for Cambrian fossil species/ In this paper non- 

 trilobitic and non-American species are included. It was hoped all 

 necessary changes in sight could go in this fourth contribution, but 

 that proved to be impossible. Several descriptive papers now in 

 press or nearing completion involve previously described species, 

 and thus make additional nomenclatural changes. Moreover, it is 

 the practice to withhold references of species to new genera where 

 undescribed species are in hand which will make better genotypes. 

 Needed changes are also withheld in instances where someone is 

 known to be at work on the faunas which contain improperly named 

 species. 



The nontrilobitic species are discussed first, grouped according to 

 classes. The trilobites are again placed in alphabetical order accord- 

 ing to genera. 



BRACHIOPODA 

 PATERINIDAE Schuchert 

 MICROMITRA Meek, 1S73 



Micromitra minutissima (Hall and Whitfield) 



Kutorgina minittissiiua Hall and Whitfield, U. S. Geol. Expl. 40th Par., 



vol. 4, pt. 2, p. 207, pi. I, figs. II, 12, 1877. 

 Kutorgina sculptilis Walcott (part), U. S. Geol. Surv. Mon. 8, p. 20, pi. i, 



fig. 7b; pi. 9, fig. 7, 1884. 

 Micromitra sculptilis Walcott (part), idem, 51, p. 341, pi. 3, figs. 5b, c, 1912. 



The Nevada form is distinct from j\I. scidptilis of Montana in 

 having coarser ribs. For this reason the old species name is restored. 



^ Resser, Charles Elmer, Nomenclature of some Cambrian trilobites, Smith- 

 sonian Misc. Coll., vol. 93, no. 5, Feb. 14, 1935 ; Second contribution to nomen- 

 clature of Cambrian trilobites, idem, vol. 95, no. 4, Apr. i, 1936; Third 

 contribution to nomenclature of Cambrian trilobites, idem, vol. 95, no. 22, Apr. 

 5, 1937- 



Smithsonian Miscellaneous Collections, Vol. 97, No. 10. 



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