One of the two large wings inside the reptile house. There are also huge holdings off reptiles in the off-exhibit part of the building - Dallas has the largest variety of venemous snakes in the country. They breed their snakes prolifically.
Thanks to a very long and friendly talk with a docent who was working in the building (showing people a ball python up close), she arranged for one of the keepers to give me a tour of the off-exhibit area.
