Optical identifications have been found for the radio sources 3C 129 and 3C 129. 1 which suggest that they are associated. Similar associations of radio sources have previously been found in the Perseus and Coma clusters. 3C 129, the sources 3C 83. 1B and IC 310 in the Perseus cluster and 5C4. 81 in the Coma cluster form a new class of radio galaxy in which the source of energy lies outside the associated galaxy. The energy originates within a nearby galaxy which is also a radio source. These systems of interacting radio galaxies are relatively common and as many as one in four of all rich clusters could contain systems of this type. The energy appears to be transmitted in the form of plasma streams with velocities which must be greater than or equal to about 0 . 01 c. The streams occupy only a small fraction of the space surrounding the active galaxy and their confinement and stability are attributed to a large scale ordered magnetic field and an associated intergalactic gas. The existence of these streams supports the hypothesis of an intergalactic medium in clusters. It is suggested that the acceleration of charged particles and the amplification of magnetic fields required to produce the radio emission, can be attributed to the effects of turbulence.