188 
SKLACHIl. 
suring about 0-022. This plate is narrow, compressed, and pointed 
at one extremity, with the crown raised into a high median angulated 
ridge. 
Form. Loc. Keokuk Limestone (Lower Carboniferous): Illinois, 
U. S. A. 
P. 2488. Typical dental plate ; Warsaw, Illinois. EnnishiUen Uoll. 
Sandalodus carbonarius, Newberry & Worthen. 
1866. Eamlalodus carbonarius, Newberry & Worthen, Pal. Illinois, 
vol. ii. p. 104, pi. X. tigs. 4, 5. 
1660. Dvltudm anytdaris, Newberry & Worthen, lorn. cit. p. 97, pi. ix. 
lig. 1. 
(P)1870. EcUodun (?) anyukuis, 0. St.John, Proc. Amer. Phil. Soc. 
vol. xi. p. 467. 
(P) 1872. Eeltodwi (? ) anyularis, O. St. Jtihn, in Tlaydeu’s Final Hep. 
U.S. Geol. Surv. Nebiuska, p. 244, pi. vi. lig. 18. 
188.6. Ovihopleurodm ca/Jyo»nr«/.s, St. John & Worthen, Pal. Illinois, 
vol. vii. p. 192, pi. xiii. figs. 0-8. 
'Fype. “ Lower” dental plate. 
A small species. “ Lower” dental plate sub-spatulate, expanded 
anteriorly, becoming narrow and poitited behind ; crown low, with 
a faint angulated ridge along the long axis of the plate near the 
straightor margin. “ Upper ” dental plate originally described 
as Diiltodus anyularis. 
Form. Loc. Coal-Measures : Illinois, Kansas, Indiana, Iowa, 
(?) Nebraska, and Missouri, U.S.A. 
P. 2489. Dental plate, wanting narrowed extremity ; La Salle, 
Illinois. Enmsl-illen Coll. 
Sandalodus Isevissimus, Newbei'ry & Worthen. 
1806. Sandalodus Icerissimus, Newberry & Worthen, Pal. Illinois, 
vol. ii. p. 104, pi. X. figs. 0-8. 
1800. Sandalodus yrandis, Newberry & Worthen, tom. cit. p. lOo, pi. x. 
fig. 9. 
1800. Ihdtodus yrandis, Newberry A W'orthen, tom. cit. p. 101, pi- i-x. 
fig. 9, 
1800. Coc/ihodus? crassus, Newberry A Worthen, tom. cit. p. 91, pi. viii. 
fig. 2. 
1860. Psammodus? semicylindricus, Newberry & Worthen, tom. at. 
p. 109, pi. xi. Hg. 4. 
IbOf). Psammodus? r/nonAou/cMs, Newberry & Worfheu, fonn «?. p. HO, 
pi. xi. fig. 0. 
