The name given by Sir Roderick Murchison to a vast series of fossiliferous strata, which lies between the non-fossiliferous slaty schists below and the old red sandstone above. The system is well developed in the region of Shropshire, etc. , once inhabited by the Silures under Caractacus, or Caradoc. —⁠ Tr. ↩

The name of an Ethiopian tribe who lived in caves and holes. Τρώγλη , a hole, and δύω , to creep into. ↩

One hundred and twenty. —⁠ Tr. ↩