  We consider the exchange relations of screened vertex operators in the sl3
Wess-Zumino-Novikov-Witten(WZNW) model in the semiclassical limit (where level
k tends to infinity). We demonstrate that the coefficients of the exchange
relations of the screened vertex operators coincide with the ones of the spider
diagrams. The spider diagrams are composed of 3-point vertices, and differ from
ordinary string diagrams.
