Oesto. 



488 



Acad. Nat. Sci. Phila. 

 1868, Coal measures.) 

 Pal. Ohio, Vol. 2, 

 1875, page 381, 384, 

 wood- cut of caudal 

 vertebrae ; plate 27, 

 fig. 5 ; 31, fig. 1 ; 32, 

 fig. 1 ; 33, fig. 2 ; 34, 

 fig. 4; 35, fig, 5.— 

 XIIL 



For other Hgures 

 seepage 486. 



Cope . PaLOhio^TL ^^^l.X^yih S. 



CEstocephalus rectidens, Cope. Trans. Amer. Philos. 



Soc. 1874; 



Pal. Ohio, 

 Vol. 2, 1875, 

 p. 386, pi. 27, 



figs. 3, 4. 

 Coal meas- 

 ures of Ohio. 

 XIIL 



Ogygia ? klotzi, Kominger. Proc. Acad. Nat. Sc. Phil. 

 Jan. 1887, p. 12. pi. 1, f. 1. A fine large trilobite unlike all 

 other Cambrian species ; differs from the type of the second 

 fauna in having an ocular ridge extending from the front edge 

 of the eye to the dorsal furrow, beside the glabella. All other 

 parts of the head, thorax and pygidium relate it more closely 

 to Ogygia than to any other generic form. The oldest Ogygia 

 species {selwyni) Salter, in the Welsh Arenig rocks, is closer 

 to O. hucTii of the Llandeilo rocks than to 0, Motzi. " It is 

 unusual that a genus showing so little variation from Ogygia 

 should occur at a much lower horizon in an area separated by 

 over 5000 miles from the area where the species of Ogygia 

 flourished at a later period," ^. ^., Wales and the Rocky Mount- 

 ains. Walcott, in Amer. Jour. Sci, Sep. 1888, p. 166. — Middle 

 Cambrian^ M, C 



'ii*-' 



