By early summer, Hogle Zoo will have a new exhibit that will contain tropical plants and eventually hundreds of delicate, colorful butterflies.

An exhibit name has yet to be chosen, but it will probably be called "Butterfly Jungle" or "Butterfly World," depending on whether the zoo decides to limit its collection to butterflies from North America or tropical areas such as Costa Rica.The glass-enclosed greenhouse, to be built on a metal frame, will be located in an area that held a pheasant pen and an otter pool. These exhibits will be relocated.

The first footings on the exhibit were laid Thursday. Located north of the monkey island, it will cost about $300,000. The framework is being constructed elsewhere, and the glass enclosure is being manufactured in New York state, said zoo director LaMar Farnsworth.

Plans for the 40-by-80-foot enclosure began after the zoo solicited the services of John Coe, Philadelphia, an expert in zoo master planning. Coe did the conceptual planning for the Great Apes Building, which the zoo built in 1984.

Zoo officials conducted internal planning sessions. Farnsworth conferred with Coe in Philadelphia last July, and the planner visited Hogle Zoo in September.

The exhibit will contain ideal lighting, heating, air conditioning and other facilities for growing a variety of tropical plants and for exhibiting butterflies. Plant selection will depend on the zoo's success in obtaining permits to obtain butterflies. It appears the zoo will concentrate initially on North American butterflies, but the exhibit may change from year to year.

For the butterfly exhibit, Hogle Zoo plans to fly in a number of pupa (a stage in butterfly development) each week, allowing them to hatch in the display.

In Utah and other areas of North America, butterflies remain in the pupa stage during the winter before changing into a butterfly. The average life span of butterflies is two to six weeks, but some species live up to six months.

"We anticipate that butterflies will be shown in the spring, summer and fall with the structure serving as a greenhouse during the rest of the year to grow bedding plants that will be used in other areas of the zoo," Farnsworth said.

The butterfly exhibit is important, the director said, because of declining numbers of rain forests, where butterflies are the main pollinators, often taking the place of bees.