[Countryboy]

This can happen when you put a foundationless frame above the bees, but don't provide them a ladder to get to the top of the frame. Usually this comb built from the bottom bar upwards is pretty, but about useless and gets damaged the first time you pull frames. Maybe being in an observation hive the bees will attach the comb to the frame and you can salvage the comb.

Bees normally start at the top of a cavity and draw comb down, but you just made a big cavity above them and they are trying to get to the top.

If you place the foundationless frame below where the bees are working, they will festoon and draw it normally.

 

[AR Beekeeper]

I have seen foundation drawn from the bottom up. Usually it was when the colony was weak and the foundation was placed in a box above brood.

 

[Joseph Clemens]

Sure, whenever they have the resources and the opportunity presents itself, bees will build comb. I've seen comb built like this and it has been most curious to see them build comb in foundationless frames with horizontal wires - they sometimes start a comb segment on a wire and build it up, down, and side to side, until it connects with other, adjacent comb segments.