Thanks for all the replies.
I am certain that they were sweet potatoes.
In BC, Canada, sweet potatoes are sold this way:
orange fleshed ones are called yams (have a redder skin, as well).
pale fleshed ones are called sweet potatoes(usually a beigy-grey coloured skin).
In reality they are both from the sweet potato family.
I have never seen a true yam here.
I believe that in other parts of Canada the lighter ones are called yams and the orange ones are called sweet potatoes.
The pale fleshed ones we get now look the same as the ones we used to get and are marked the same but they taste differently.
My Mom (she has an excellent memory) says the same thing.
I will look for the Japanese sweet potatoes to try.
Has anyone had the drier, chestnut-tasting, not-so-sweet potato? If they still exist maybe I can grow some.
When I was in New Zealand in the 70's I really enjoyed the kumara they had there. I have never seen them here, though.