4 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 97 



seems that these faunas represent faunal subzones or possibly facies 

 developments, but for purposes of correlation it is necessary to treat 

 the faunas of the Rennie and Lakeview formations as a unit. 



The fossils in the Rennie shale are clearly related to those in the 

 Stephen formation.' Margaretia, Elrathia, Glosso pleura, and the par- 

 ticular form of Hyolithes are definite relatives of species in the 

 Stephen. On the other hand Vanuxemella and Alhertella are more 

 characteristic of the older Ptarmigan formation of the Canadian Rock- 

 ies. The Lakeview is also related to the Stephen, particularly by the 

 Agnostus, Oryctocephahis, and Zacanthoides. The numerous species 

 of Alokistocare are found more commonly in other Middle Cambrian 

 formations than in the Stephen. 



Close connection exists between the Lakeview and the Spence shale * 

 of southern Idaho. Pagetia and the rare trilobite Utia curio indicate 

 that these two formations are identical in age. The other genera, 

 both in the Lakeview and in the Rennie, occur in the Spence also. 



DESCRIPTION OF THE FOSSILS 



The identifiable material is described and illustrated as completely 

 as possible. In order to avoid unnecessary printing, locality numbers 

 are given with the descriptions and in the plate legend. A full descrip- 

 tion of the two localities is given below. 



Locality 37m : Middle Cambrian, Rennie shale ; headwaters North 

 Gold Creek, south side of Packsaddle Mountain, east of Pend Oreille 

 Lake, Idaho. 



Locality 37n : Middle Cambrian, Lakeview limestone ; cement mine 

 just north of Lakeview, Pend Oreille Lake, Idaho. 



MARGARETIA Walcott, 1931 

 MARGARETIA ANGUSTATA, n. sp. 



Plate I, fig. 2 



A number of narrow flexible tubes have a surface roughened by 

 elongate depressions typical of Margaretia. Compared with the geno- 

 type, M. dorus, as well as species in process of publication, M. angus- 

 tata is considerably smaller in size, averaging less than one-fourth the 

 diameter of the smaller specimens of the other species. 



Locality 37m. 



Holotype. — U.S.N.M. no. 95019. 



* Walcott, C. D., Amount Stephen rocks and fossils. Canadian Alpine Journ., 

 vol. I, no. 2, 1908. 



* Walcott, C. D., Smithsonian Misc. Coll., vol. 53, no. i, p. 8, 1908. 



