The process whose specific outcome is the progression of cardiac jelly over time, from its formation to the mature structure. The cardiac jelly is an acellular gelatinous matrix secreted by the myocardium and plays a central role in the septation of the heart. [ http://purl.obolibrary.org/obo/go/references/0000094 http://www.ncbi.nlm.nih.gov/pubmed/10645959 http://www.ncbi.nlm.nih.gov/pubmed/19703439 GOC:BHF GOC:TermGenie GOC:rl http://www.ncbi.nlm.nih.gov/pubmed/16314491 ]