I recently added this one to my collection (and I love it. Very nice shape). The shape pattern is called "Odeon", probably designed in the '90s as it was a part of the 1997 catalogue. At the time, P&P offered engraved versions of a certain shapes as a variation. The Odeon vase was also available without the engraved leaves.
If you like to see more P&Ps, check my sig, I have a special album with only Peill & Putzler vases on Picasa (it's become my first glass collectiong specialization).
Astrid