| Date | Day | Commons day type | Commons praying | Lords day type | Lords praying |
|---|---|---|---|---|---|
| Wednesday | 18th | Prorogation | False | Prorogation | False |
18th September 1878 is in the prorogation between the 5th and 6th sessions of the 21st Parliament, being the 5th prorogation of that Parliament.
Papers laid during this prorogation are reported by both Houses in the 6th session of the 21st Parliament.