  The decay of heavy orthoquarkonium into quark-antiquark pair and two gluons
is considered. The differential probability of the decay in the tree
approximation is calculated and the probability distributions of quarks and
gluons are obtained. The collinear enhancement of the bottomonium decay is
shown to take place at the u\={u}--, d\={d} and s\={s}-- pair production and to
be absent at the c\={c}-- production. Some other peculiarities of the
considered decays are discussed. (Published in Mod.Phys.Lett A 9 (1994) 115).
