Poly. 



734 



XI 



Polyrhizodus pisaensis, St. John & Worthen, Geo. Sur. 



111.5 ^^^^ ^5 18'i'^) page 



i 6 S. - 





/K 386, plate 13, figs. 12 a, 5, 

 I^© <?9 concave face, convex 



nearly perfect, and quite unique fish-tooth, found in the War- 

 saw limestone heds^ a mile above Pisa creek. 111. ^XI? 



Polyrhizodus ponticulus, Newberry & Worthen, Geo. 



Sur. 111., Vol. 2, 1866, page 51, 

 plate 3, figs. 11, 11 a^ natural sizet 

 f $' front view, and profile'; the roots 

 .^tfir of this fish-tooth curiously sug- 

 gests a stone arched bridge, whence its name. Classed with 

 McCoy's Irish P. magnus^ but not his P. pusUlus. Chester, 

 111. Chester limestone. XI, 



Polyrhizodus porosus, Newberry & Worthen, Geo. Sur. 



111. Vol. ,2, 1866, page 49, plate 3, 

 figs. 9, 9^, natural size^ hind face 

 and section of the largest found 

 fish tooth, thick and massive, dif- 

 fering somewhat from McCoy's 

 Irish P. magnus; Burlington., and Quincy, 111., Burlington 

 limestone (next to the bottom division of subcarboniferous.) 

 XL 



Polyrhizodus williamsi, St. John & Worthen, Geo. Sur. 



111., Vol. 6, 

 187 5, page 



XI. 



Geo/.J//,i^l2,n:^ 



a 



cL . 







.J* 





#no. 



. 25"b 



c O Ji 



1^^^ 



^S^S^ 384, plate 13. 



(leoLSIl.VG/.^yi.nA.c^^VoLIP fig. n^, con- 

 cave face, showing toothshaped root of this tooth ; 5, crown and 

 triturating convex surface ; c, profile ; plate 10 A. figs. 23«, 5j 

 Boonville and Keokuk, Mo. and Iowa. Upper fish-bed of the 

 Keohuh limestone, XI, 



{Polysporia) Lepidostrobus mirabilis, Newberry, Pal 

 Ohio, Vol. 1, 1873, page 362, plate 41, fig. 5, a'^'cone, showing 

 the arrangement of the seed cases (sporangia); ha,, a detached 

 sporangium containing microspores ; fig. 6, summit of cone sur- 

 rounded by a mass of spores escaped from the sporangia, and 



