A fourth step for {TAIL ~ a hybrid cross} may comprise cross pollination between {HEAD ~ the first and second parent pea plants} 
A fourth step for { TAIL ~ a hybrid cross } may comprise cross pollination between { HEAD ~ the first and second parent pea plants }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD