walcott.] PALEONTOLOGY APPALACHIAN. 153 



In 1886 Prof. William B. Dwight announced tbe discovery of the 

 fauna of the Potsdam zone in limestone near Poughkeepsie, New York. 

 He gives a list of eleven species as follows : l 



Lingulepis pinnaformis. Ptyclioparia (Conocephalites) n. sp. 



LiDgulepis minima. Dikelocephalus sp. 



Lingalepis acuminata (probably). Ptychaspis sp. 



Obolella (Lingulella) prima. Stromatocerium ? 



Obolella sj). Remains of crinoid columns. 



Platyceras sp. 



The review of the Olenellus or Lower Cambrian fauna by Mr. C. D. 

 Walcott in 1886 2 resulted in the description of the following species 

 from Vermont : Climacograptus f emmonsi (p. 93), Orthisina transversa 

 {p. 121), Scenella ? varians (p. 127) and Microdiscus par~keri (p. 157). This 

 was followed in 1887 3 by an account of the discovery of a number of 

 new species of fossils from the Upper Taconic slate of Emmons in 

 Washington County, New York. The new species described are as 

 follows : 



Lingulella granvillensis. Leperditia (I) dermatoides. 



Linuar8sonia taconica. Microdiscus connexus. 



Orthis salemensis. Olenoides foj Ji 



Modiolopsis (??) prisca. Solenopleura (?) tumida. 



Hyolithellus micans, var. rugosa. Ptychoparia (!) fitchi. 



Aristozoa rotundata. P. (?) clavata. 



In describing a section of the Cambrian rocks in northern Vermont 

 notice is taken by Mr. Walcott of the occurence in the upper beds of a 

 fauna resembling that of the Upper Cambrian or Potsdam zone. 4 



In a paper announcing the discovery of the fossiliferous strata of the 

 Paradoxides zone at Stissing Mountain, Dutchess County, New York, 

 Prof. W. B. D wight 5 identified Eyolithes billingsi f (p. 143) and described 

 as new Leperditia ebenina (p. 144), Kutorgina stissingensis (p. 145), and 

 Olenoides stissingensis (p. 147), correlating the fauna with that of the 

 Middle Cambrian of the Eocky Mountain province. 



In a review of the Lower Cambrian fauna by Mr. C. D. Walcott, pre- 

 pared for the Tenth Annual Report of the U. S. Geological Survey, a 

 number of new species and genera are proposed, most of which are de- 

 scribed in a preliminary paper published in the Proceedings of the U. 

 S. National Museum. 6 These are Archceocyathus dicighti (p. 34), Plan- 



1 Recent explorations in tbe Wappinger Valley limestone of Dutchess County, New York. Xo. 5; 

 Discovery of fossiliferous Potsdam strata at Poughkeepsie, New York. Am. Jour. Sci., 3d ser., vol. 

 31, 1886, p. 131. 



2 Second contribution to the studies of the Cambrian faunas of North America. U. S. Geol. Survey, 

 Bull. No. 30, 1886. 



J Fauna of the " Upper Taconic " of Emmons, in Washington County, New York. Am. Jour. ScL, 

 3.1 ser., vol. 34, 1887, pp. 187-199. 



4 Second contribution to the studies of the Cambrian faunas of North America. U. S. Geol. Survey, 

 Pull. No. 30, 1886, pp. 17, 19. 



•Recent explorations in the Wappinger limestones and other formations of Dutchess County, New 

 York. Am. Jour. Sci-, 3d ser., vol. 38, 1889, pp. 139-153. 



'Descriptive notes of new genera and species of the Lower Cambriam or Olenellus zone of North 

 America. TJ. S. Nat, Mus. Proc, vol. 12, 1889, pp. 33-46. 



