Found it in an undated Miller & Richards catalog from the University of California collection, digitized by Microsoft. Good luck finding a digital version: the original typeface was named Trajan (pp. 317 et seq.). Go figure...
Note: the specimen book doesn't show an ampersand for the Roman, but it does for the Bold weight, and the design matches the second ampersand shown.
This appears to be the same book; Trajan specimens start on page 317…
http://www.archive.org/download/printingtypespec00millrich/printingtypes...
Captured from web.archive.org on 23 Aug 2013. view this capture