J,

As you
suggest, the variegated cultivar is C. Bengal Tiger (Pretoria) or C. Tropicanna
Gold. We need to wait for the first bloom to confirm the ID. Unfortunately
there are several candidates for the yellow blooming cultivar.

I am betting
on the fact that the yellow has reddish spots in the bloom but that only would slightly
reduce our guess.

Being a
dwarf cultivar (if) also eliminates a number of choices and your plant appears
to be dwarf and healthy.

Because several of our commercial nurseries
are becoming concerned with canna virus they have been using some of the F-1
seed strain cannas now available. Many of these were developed by Takii in both
the US and Europe. You might compare your canna to two of the yellows developed
by them. Check out C. ‘Tropical ™ Yellow’. America Takii’s F1 Hybrid Canna Seed
Collection.

http://www.takiiseed.com/goods_list/goods_list_7.php?p=26&called=ca..&sort=code&disp=10&now_page=26&m_no=Tropical

You
also need to compare it to Takii’s (Europe) F1 Hybrid Canna Seed Collection.
Compare your canna to C. Cannova Yellow.

http://www.ballseed.com/PlantInfo/?phid=013306980003120

Please
understand these suggestions are only possibilities but may be a starting
point.

Kent

Thanks Kent!