Cold fusion products from the electrolysis of heavy water have been directly measured by using a thin palladium foil. Several anomalous traces have been clearly recorded on nuclear emulsions. Some traces have meshlike structures, which are classified into two types: (a) ones associated with ring traces that are caused by the gravity decay of quadneutrons and (b) ones with no ring traces. The mechanisms that form these meshlike traces are discussed in terms of the Nattoh model. It is inferred that multiple-neutron nuclei such as quad-neutrons, covered by itonic mesh and iton beads, are born during cold fusion. Furthermore, other anomalous traces suggest the production of a new heavy particle during gravity decay.