Quotes from Western Fathers on the epiclesis in the West:
"Justin Martyr (Rome, m. between 163 and 167)
Apol. l. Ixvi:
For we do not receive these things as common bread or common drink; but as Jesus Christ our Saviour was made flesh by a word of God (διὰ λόγου Θεοῦ - dia logou Theou) and had flesh and blood for our salvation, so we have been taught that the food which is made Eucharist through a word of prayer that comes from Him (τὴν δι’ εὐχῆς λόγου τοῦ παρ’ αὐτοῦ εὐχαριστηθεῖσαν τροφήν - ten di euches logou tou par autou eucharistetheisan trophen), from which by change [κατὰ μεταβολὴν - kata metabolen, i.e. by metabolism.] our blood and flesh are nourished, are the flesh and blood of the same incarnate Jesus Christ.
Irenaeus (Lyons, d. 202-3)
Haer. i. xiii. 2:
Pretending to make Eucharist of cups mixed with wine, and extending to a great length the word of invocation, he (i.e. the heretic Marcus) makes them appear purple and red, so that it seems as if Charis [One of the emanations in the Valentinian Gnostic system.], one of those beings who are above all things, distilled its blood into that cup at his invocation.
Ibid. iv. xviii. 5:
For as bread from the earth, on receiving the invocation of God, is no longer ordinary bread, but Eucharist, &c.
Ibid. v. ii. 2:
When therefore the mixed cup and the bread that is made receives the word of God, and becomes the Eucharist of Christ's blood and body, &c.
Ibid. v. ii. 3:
(These fruits of the earth) by God's wisdom become fit for man's food, and now, receiving the word of God, become a Eucharist, which is Christ's body and blood.
Hippolytus (Rome, d. 235) quotes in Philosophumena, vi. 39 the first passage of Irenaeus.
Ambrose (Milan, d. 397)
De Sp. Sanct. in. xvi. 112:
He who with the Father and the Son is by the priests named in baptism, and invoked in the oblations.
Optatus (Africa, d. 400)
De schism. Donat. vi. i: ...
the altars of God, on which you (the Donatists when Catholics) at one time offered, on which the vows of the people and the members of Christ were borne, where God Almighty was invoked, where the Holy Ghost descended in answer to prayer; whence the pledge of everlasting salvation and the safeguard of faith and the hope of the resurrection was received by many, &c.
Augustine (Africa, d. 430)
De Trin. in. iv. 10:
That which is taken from the fruit of the earth and consecrated by the mystical prayer we duly receive for our spiritual health in remembrance of the passion of our Lord on our behalf. When this is by the hands of men made to assume that visible form, it is not consecrated so as to become so great a sacrament except by the invisible operation of the Spirit of God.
Isidore (Spain, c. 636)
De eccles. officiis, i. 15 (describing the seven prayers of the liturgy):
Then comes the sixth, the 'Conformation' of the sacrament, that the oblation which is offered to God, being sanctified by the Holy Spirit, may be conformed to the body and blood of Christ.
Ibid. i. 18:
But these (bread and wine), while they are visible, having nevertheless been sanctified by the Holy Ghost, pass into the sacrament of the divine body.
The following, generally attributed to St. Isidore, is probably much later.
Etym. vi, 19:
We call it the body and blood of Christ be cause, though it is of the fruit of the earth, it is sanctified and made a sacrament, by the invisible operation of the Holy Ghost.
Gelasius (Rome, d. 496)
Ep. ad Elpidium:
For how shall the heavenly Spirit, on being invoked, come to the consecration of the divine mystery, if the priest, even he who prays Him to be present, is found to be full of guilty actions?
Fulgentius (Africa, d. 533)
Ex Frag. xxviii ex Lib. viii contra Fdbianum:
When at the time of the sacrifice we make commemoration of his death, we ask that love be given to us through the coming of the Holy Spirit, &c.
Ad Monimum, ii. 6:
Why then, if the sacrifice is offered to the whole Trinity is the sending down of the Holy Spirit alone asked for to sanctify our oblation, as if, so to speak. God the Father, from whom the Holy Spirit proceeds, cannot sanctify a sacrifice offered to him, &c. ... And so when the Church asks that the Holy Spirit should be sent upon itself from heaven, it is asking that the gifts of love and unanimity should be given to it by God; but when can the holy Church, which is the body of Christ, more fittingly ask for the coming of the Holy Spirit than for the consecration of the sacrifice of the body of Christ?"
From Appendix C, Handbook to the Christian Liturgy, James Norman MA, 1944 (SPCK)