The small prison-like brick and steel bar cages constructed by the WPA were no longer considered appropriate environments for many of the animals displayed in them.
They are transported in vehicles consisting of big cage constructed on bed of a straight (as opposed to semiarticulated) truck.
Though some facilities, such as the "ape room" are recent facilities, most animals are housed in concrete and steel cages constructed between 30 and almost 90 years ago.
One was a cage constructed of woven slats of wood, suspended from the ceiling; within it five or six young trees hovered and fizzed, immature branches whirling.
The huge cage, constructed with metal bars to allow visibility from all sides, was set atop a low red platform.
He brought out a curious cage constructed of bamboo.
All that remained now was a skeleton, an empty cage constructed of God-knew-what.
Photos from the early 1930s show cages constructed of chain link fence and iron bars, with very little vegetation planted near the exhibits.
On each flatbed was a cage constructed of steel piping.
They are both "steel baskets" or "cages" constructed with a special structural steel known as "architecturally exposed structural steel".