A careful inspection and analysis by staff members of the Arnold Arboretum has established the identity of the trees along Memorial Drive that are to be moved for underpasses as "a hybrid of long standing between an American and Eurasian species of Platanus."

"The common name for this tree in general use is London plane," according to Bernice G. Schubert, associate curator of the Arboretum, "but the use of common names is virtually meaningless." She appealed yesterday for use of the Latin nomenclature of the hybrid Platanus acerifolia.

This hybrid of Platanus was "originated perhaps as early as 1670," Miss Schubert explained. Choosing a common name for it is complicated, she said, since "it is more generally planted under the name of the oriental plane than the true Platanus orientalis."

In any case, it is now clear that the doomed trees are not examples of the native North American sycamore, which is found primarily in the Midwest.

While botanists were examining the identity of the trees that must be moved, Edward L. Bernays, chairman of the Citizens Emergency Committee to Save Memorial Drive, was delighted that "confusion about what they are may bring greater interest in saving the trees."

Bernays said yesterday that his Committee had written to the British Embassy in Washington "inviting a member of the British Horticultural Society to come to identify the trees and determine for all time what they are."

"Since it has also been said that the trees may be oriental planes, brought here in 1894," Bernays said, he has also written to the Embassy of Thailand for an assessment of the Mem Drive trees' identity. Siam has often been regarded as the home of the oriental plane, he said.

As Miss Schubert said, "It matters little whether we 'Bolster the Buttonwood,' 'Preserve the Planes,' or 'Save the Sycamores' so long as the trees of Platanus along Memorial Drive are protected."