Each side of the cubiculum, except that of the entrance, usually contains a recessed tomb, either a table-tomb or an arcosolium.
The cubiculum was originally designed for the reception of a very limited number of dead.
Another motive for multiplying the number of graves operated when the cubiculum contained the remains of any noted saint or martyr.
Each cubiculum was usually the burying-place of some one family, all the members of which were interred in it, just as in the chantry-chapels connected with medieval churches.
Explorations conducted in the cemetery of Domitilla in 1897-1898 brought to light a fine double crypt with frescoes representing Christ seated between six male and female saints; also an inscription relating to a new saint (Eulalius) in a cubiculum of the 3rd century.