Yes Gallego done a very nice job for design varieties. For transitional I will look if someone explained well. In fact we have on the quarter from 1932 to 1999 only one transitional which it is major. This happened in 1964 and 1965.
1964 we have coins struck in clad
1965 coins struck in silver.
A second one which I never see, but someone told me apparently exist is in 1998 when was struck coins with the Observe for 1999.
Hope this help.