In the lower left corner of the photo, note that the gall that is pointing away has a pale circle in the upper third of the gall. According to http://www.microleps.org/Guide/Momphidae/ "When the larva finishes feeding, it gnaws almost entirely through the wall of the gall in a small circular area that will serve as an 'emergence window.' The white silk cocoon the larva spins inside the gall attaches to the emergence window.