120 



Rafinesqcina Cebes, Billings. (Sp.) 



Strophomeva Ceref:, Billings. .1860. Canad. Nat. and Geol., vol. V., p.54. 



" ..1862. Geol. Surv. Canada, Pal. Foss., vol. I., p. 119. 

 Probably a variety of if. altemata (Conrad). 



Lower beds, T. C. Weston, 1884 : two perfect and several imperfect 

 specimens. 



Lept^ena nitens, Billings. (Sp.). 



Strophomena nitens, Billings. .1860. Canad. Nat. and Geol,, vol. V., p. 53. 



" " " . .1862. Geol. Surv. Canada, Pal. Foss., vol. I., p. 118, 



figs. 97 and 97 a. 



Lower beds, Dr. R. W. Ells, 1875, and T. 0. Weston, 1884 : abundant. 



On page 413 of "the Lower Silurian Brachiopoda of Minnesota," * by 

 N. H. Winchell and Charles Schuchert, the following passage occurs. 

 " In Anticosti Strophomena nutans, Billings, occurs, which as far as ex- 

 ternal characters are concerned, appears to be identical with specimens 

 from Wilmington, Illinois, examined by one of the writers. The interiors 

 of these show them to be a species of Leptcena, Dalman, and they are 

 a,pparently closely related to L. unicostata." The specimens of S. fdtens 

 from Anticosti in the Museum of the Survey do not show any of the 

 characters of the interior of either valve, but, in a perfect example of that 

 species from Charleton Point, there is a single rib, larger than any of the 

 others, in the median lino of the ventral valve, as in the typical form of 

 L. unicostata. 



Oethis (Dinoethis) proa vita, Winchell and Schuchert. 



Orthis •iuiquadrata, Whiteaves (as of Hall) . . 1880. Geol. Surv. Canada, Rep. Progr. 



1878-79, p. 50 C. 



Orthis proavita, Winchell & Schuchert 1892. Amer. Geologist, vol. IX., p. 290. 



1892. Bull. Minn. Ac. Nat. Sc, vol. III., 



p. .332, pi. 5, figs. 18-21. 



" " 1893. LowerSilur.Brach. Minn.,p.431, 



pi. .32, figs. 51-57. 



Lower beds. Dr. R. W. Ells, 1875, Dr. R. Bell, 1879, andT. C. Weston, 

 1884 : abundant, large and well preserved. Upper beds, T. C. Weston, 

 1884: numerous good casts of the interior of one or both valves. The 

 late Mr. E. Billings, who had seen the specimens collected by Dr. Ells 

 at Stony Mountain, regarded them as a coarsely ribbed variety of Orthis 

 subquadrdta. Hall. 



*Extraoted from vol. III., of the Final Report of the Minnesota Geological Survey 



