Today being the feast of the apostles Philip and James, it's a Roman Canon day according to my 'Plan for the minimum use of Eucharistic Prayer I,' which I recommend to all of my brother priests as a means of recovering this venerable prayer from having been (in some places) marginalized in the modern Roman liturgy.
Thinking about this last night was the occasion of thinking on something I had never noticed. Even after almost twenty years as a Catholic and almost five as a priest, I still make personal discoveries in the liturgy. Some of this comes from the shallowness of my own prayer and spirituality, but it also comes the amazing richness of the liturgy.
Today it was St. James in the Roman Canon. Both the apostles James are commemorated in the Canon, but I had never thought of which was which. It's fairly obvious with just a thoughtful look: the first James comes right before John, suggesting that this one is James the Greater, the brother of John. The second James is next to Philip, matching the liturgical association they have on this feast, and so is James the Less. Of course it's all as easy as the first being James the Greater and the second being James the Less, but my point is that I had never thought about it before. If I had prayed as far as the Jameses, I was probably looking ahead in anxiety as I hoped to get through the tongue-tying middle of Lini, Cleti, Clementis, Xysti, Cornelii, Cypriani, Laurentii, Chrysogoni/Linus, Cletus, Clement, Sixtus, Cornelius, Cyprian, Lawrence, Chrysogonus.
I have always been fascinated by the more or less insoluble question of whether or not James the Less was the same James who was bishop of Jerusalem. Whoever designed the last parish I worked in seemed to think so; the twelve apostles (with Paul replacing Judas, sorry Matthias) were painted at the tops of the columns, and James had a very nice miter on.
There are also two Peters in the Roman Canon.
One can read about the saints of the Canon in lots of places, but because it is such a useful and attractive site, I suggest the article posted at Sancta Missa.