PSAM. 



788 



yNovlhrt, 

 Vol.2. 



1838. New. & W. Geo. Sur. 111., Vol. 2, 1866, page 107, plate 

 11, figs. 1, la, 15, natural size^ surface, side and end, of a fish 

 tooth (undistinguishable from^those described by Agassiz, in 

 Poissons fossils, Vol. 3, p. 112; Atlas Vol.3, plate 13), found at 

 Chester, 111., in the Chester limestone, XI. 



Psammodus reticulatus, Newberry and Worthen, Geo. 



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

 109, plate 11, figsS and 5«, 

 natural size,, upper sur- 

 face and cross section of a 

 fish tooth, wrinkled cross- 

 wise, like jP. Tugosus of 

 Agassiz. ( See also Vol. 7, 

 1883, page 224, plate 19, 

 figs. 3a, to 5c.) Chester, 111. Chester limestone, XT. 



Psammodus rhom-boidens, Newberry and Worthen, Geo. 

 V >. Survey of 



111., Vol. 2. 

 18S6, page 

 110, plate 

 11, figs, 6^ 

 6a, the up- 

 per surface 



Geol, SlLVolXPU-f. ^"^ «i<i« «f 



fish -tooth, 



from the Keokuk limestone of Illinois. XI, — S. A. Miller says 

 in his latest edition of N. A. Geol. & Pal. 1889, that this is a 

 pynonym for Sandalodus Icevissimus, 



Psammodus rugosus, Agassiz. Kecherches Poiss. Foss. 



1838, New. & W., Geo. Sur. 111., 

 Vol. 2, 1866, page 108, plate 11, 

 figs. 3, 3 a, natural size^ upper 

 surface and side view of a small 

 tooth, doubtfully separated from 

 P. porosus,, because the surface 

 is coarser and rougher, and because they occur in two forma- 

 tions which have few species in common. McCoy regarded 

 Agassiz's two species (porosus and rugosus) as mere varieties. 

 Alton, 111. St. Louis limestone, XI, 



MolJliTL.PiXl. 



