1. The chapel. In 1869 it was restored by the Roman architect Martinucci for the order and at the expense of Pius IX (1846-1878) who wanted to honor the three great protectors against the plague and infectious diseases: st. Sebastian, st. Roch and st. Martha. The epigraph, which is in the right wall, says: PIUS IX P. M. / PRINCEPS OPTIMUS BENEFICENTISSIMUS / AEDICULAM HANC SEBASTIANO MARTYRI SACRAM / PICTURIS CULTUQUE SPLENDIDIORE INSTAURAVIT, ORNAVIT / AC SS. ROCHO ET MARTHAE DICAVIT / ANNO MDCCCLXIX.
2. The paintings. Instead of the two original lateral canvases, we believed they were of the good school of the sixteenth century, which depicted the Roman saints Lawrence and Sebastian, today there are two frescoes by Guido Guidi (1835-1919), Roman painter pupil of Minardi, representing st. Roch and st. Marta. At the base of this fresco is written: CHRISTUS DOMINUS, AUCTOR CHARITATIS, FONS VITAE, MISEROS AEGROTOS, MARTHA DIVINI SERVATORIS HOSPITA DEPRECANTE , SANITATE RESTITUIT. On the altar there is St. Sebastian, performed in 1614 by Giovanni de ‘Vecchi (1536-1615), pupil of Raffaellino del Colle, which was restored in 2000. In the rounds of the cupola, most of which are made of gold, four kids holding in hand Cross, chain, arrow, palm and crown, alluding to his martyrdom and glory of st. Sebastian. In the lunettes you see the emblem of Pius IX and in the pendentives the monogram of Christ in the middle of the palm crown.
3. Cenotaphs. On the side there are four white marble cenotaphs. On the right, one dedicated to Vincenzo Cini died in 1845 and his son Raffaele; The other dedicated to Pellegrina Cini and her daughter. They are the work of Adam Tadolino. In the left, one to Archbishop Pietro Filippo Boatti, who died in 1836 by the sculptor Ceccarini; The other of Filippo Boatti, who died in 1861.