A survey of the aerial parts of A. ma ju s has established the presence of several protein amino acids together with one non-protein amino acid. Antirrhinzim or Antirrhinon was described by D~OSCORIDES; GERARD (1597) recorded that it possessed magical properties and it is also reported to be an hysteric and of value in ophthalmia (REDWOOD, 1848). Leaves of A. maius have been used for their bitter and stimulant properties and applied in poultices to tumours and ulcers.Chemical investigations have concentrated on the elucidation of the structure of pigments and investigation of transmission of flower colour; more recently iridoid glycosides have been isolated (SCAPARTI and GUISO, 1969). Alkaloids have been investigated and 4-methyl-2,6-naphthyridine has been isolated (HARKISS and Swrnr, 1970; HARKISS, 1971). Infusions of the plant have been shown to possess cardiotoxic, hypotensive and sedative actions (NASYROV, 1971). This analysis of amino acids was carried out as a preliminary step in the investigation of a biosynthetic route for the 4-methyl-2,6, naphthyridine base.