Justin Martyr seems to imply that the consecration is effected by the Commemoration of Christ’s own words in the Institution:  “We have been taught,” he says, “that the food which is blessed by the prayer of the word which comes from Him (τὴν δι᾽ εὐχῆς λόγου τοῦ παρ αὐτοῦ εὐχαριστηθεῖσαν τροφήν), and by which our blood and flesh are by transmutation nourished, is the Flesh and Blood of that Jesus who was made Flesh.”  He gives no separate Invocation of the Holy Ghost, but this may have been supplied in the “praise and glory” or in the “prayer and thanksgivings” sent up “to the Father of all through the name of the Son and of the Holy Ghost Apol. I. cc. 65–67..”