The teeth from Maryland's Astrodon were cut open in 1858 & revealed this pattern, hence its name
& O. R. R. cut at Savage, 
.... Maryland is, therefore, closely related in its physiographic fea- tures to the 
States ..... tooth in the latter beds, which was described under the generic name 
...... were described by linger from this area as early as 1843/ and again in 1858.