This study documents and analyzes cyclic patterns used as melodic vocabulary in John Coltrane's improvisations from compositions of 1965 to 1967. The analysis is categorized in two distinct sections. The first section analyzes melodic vocabulary that is derived from the cycle of descending major thirds progressions found in the compositions of 1959 to 1960. The second section analyzes melodic vocabulary that is derived from Nicolas Slonimsky's Thesaurus of Scales and Melodic Patterns using the theoretical terminology incorporated in the treatise. Musical examples consist of patterns from the Thesaurus and excerpts from selected improvisations of John Coltrane as transcribed by Andrew White. Important scholarly contributions relevant to the subject by Carl Woideck, Lewis Porter, David Demsey, and Walt Weiskopf are included. Every effort has been made to cite interviews with musicians and commentaries by writers contemporary to that period of time with special emphasis on the important influence of Thelonious Monk, Miles Davis, and Ornette Coleman. Chapter headings include: Literature Review and Methodology; Thelonious Monk, Miles Davis, and Ornette Coleman: Converging Influences; Analysis: Coltrane's Major Thirds Harmonic Cycles Used as Melodic Vocabulary; Interval Cycles in Coltrane's Melodic Vocabulary Based on Patterns from Slonimsky's Thesaurus; Summary and Conclusion.